The Coral Family

A fictional story about cold-water corals in the dark deep sea. The corals catch food carried by the current. People change their habitat and try to help them. After the last human visit, the family lives on with what has been left behind. The calendar years keep moving forwards without starting again. The unusual abilities and future dates belong to this imagined story.

Once upon a time, a coral family lived deep in the dark, cold sea. Polyps sat on its branches: tiny animals with feeding tentacles. They caught food from the current. The family's skeletons were white, and the corals were healthy. Our story now follows many generations into an imagined future. There, some descendants will do things that are only possible in stories today. Ships sailed far above the family. On land, people built houses, roads and factories. What they released into the air and water did not stay above: heat and waste could reach the dark sea too.

For a long time, the sea remained full of neighbours. Ships sailed high above them. People caught fish, built harbours and extracted oil and gas from the seabed. At first, the family noticed only what reached the depths. Its larvae still found new rocks and became new colonies. The branches above the sand were yellow and pink. A jellyfish drifted slowly past; beneath it, a small fish darted through a fork. Starfish were there too. The current could hardly find a gap where nobody lived. ‘Who lives here?’ it murmured. The answer came as a flick of a fin, a searching arm and a tiny open crown of polyp tentacles.

People kept working above the sea, but some deep rocks were still untouched. An almost unchanged colony could grow there. Pale skeletons and open polyps belonged to a living home that still needed protection from disturbance. A little further on stood a relative that looked much like the first pale corals. Only a blue and pink crown near its base stood out. The current curved around its rock, and many polyps opened together. Here the family needed no great transformation. As long as water and food arrived, even an almost unchanged branch could keep growing.

People now hunted around deep reefs too, using diving equipment. Where they struck animals and stirred up the seabed, the neighbourhood changed. The family could not leave its place to escape the hunting or the cloud of particles that followed. A diving lamp shone across the turquoise branches. Then a person in a heavy pressure-resistant suit arrived, and a harpoon shot through the water. The shark spun round; suddenly the branches fell silent. The colony stayed fixed to its rock. It could not move away. Long after the light had vanished, stirred-up particles still danced around its polyps.

Shipping routes grew busier, and fishers kept losing nets. A net sank even though nobody above was pulling it. Below, it caught on branches; each surge of water could rub its threads against the reef. A ship rumbled above the reef. Something orange sank and caught between the branches: a piece of net. The blue colony could not shake it off. The current tugged at it, pulled it tight and let it go again. A small fish swam around it in a curve. From then on, this strange object was part of every day at the family reef.

A fishing boat had lost part of its line. The thin piece sank deeper than people could see with their eyes. The current carried it along and finally pushed it against a coral on the seabed. A dark thread hung beside a pale coral. When the water pulled, it swung against a branch. There, the polyps had drawn in their tentacles. On the other side, they could keep feeding. The thread stayed caught for a long time. For the little animals, it was a large obstacle, although it was barely thicker than a hair.

People tipped things they no longer wanted from a boat into the sea. The particles vanished from sight but kept sinking. At the reef, they settled between polyps that had to catch their food there. A boat passed over the relatives. Brown particles sank from its belly and fell between the branches. Some polyps withdrew; others remained covered in dirt. The current brought food too, but it was hard to reach. When the boat disappeared, its cargo stayed below for a long time. One branch took hours to become clear again.

People reached the family reef with diving equipment and lights. Some wanted to catch animals; others wanted to check their condition. A careful visitor could observe without breaking branches, but care alone could not protect them from changes in the wider sea. A person in a heavy pressure-resistant suit stopped beside the brown relative. Next to its large branches, the visitor looked tiny. Behind the visor, the person looked up, then down at the base. The polyps carried on as always: they stretched into the current. When the visitor left, nothing had been taken and nothing left between the branches.

Above the sea, people argued about fishing and protection. Some wanted to spare the seabed; others wanted to keep working there. Below, protected places and damaged reef belonged to the same dark habitat, linked by the same current. At the reef's edge, two worlds met. A lamp bathed the colony's left side in red light; on the right, the branches stayed dark. The current brushed through both halves. Above, people argued about what the sea deserved. Below, a polyp opened its tentacles. It needed no grand words, just water, food and a safe place.

People now measured the effects of their warming world deep below too. Their signs showed temperatures far too high for the original cold home. The numbers signalled danger, not a friendly new normal. People hung small temperature signs beside the branches. The numbers told of water much warmer than the first cold-water corals' home. Distant descendants lived here in a changed world. One polyp withdrew; another stayed open. The helpers measured again. Colour alone could not tell them how the two were doing.

People no longer measured only at the surface. Deep below, cool and warmer flows met at the same rocks. The warming world affected these routes, but a colony could not choose which current reached it. Two currents met beside a pale relative. A cool blue ribbon passed above, a warmer one below. The water never stood still. Sometimes one flow reached the branches, sometimes the other. The polyps opened and closed. A helper checked the temperature in several places before deciding where the youngest descendants might find a better home.

People dragged heavy nets over the seabed. Whole coral bushes could break, whatever their colour. The grey relative was not dead because it was grey; danger came from the equipment all around. A grey relative also belonged to the family. Its polyps were pale, with only one lower down that was yellow. Water flowed between its branches. A tiny animal touched a feeding arm. The polyp held it fast and drew itself in. This unassuming coral was alive and eating too, right among its colourful neighbours.

Ships and coastal cities lay far above this place, yet their traces reached here too. Deep below, currents came from different directions. The pink, blue and green parts of the family shared the same water and food. A relative was pink above, blue below and green on a side branch. A fish swam around the pale part, then close above the darker base. Polyps on both halves reached for the same passing particles. The family had gained many colours, but its meals were still small. Today, enough water reached every side, and all the crowns had work to do.

Different substances entered the water from coastal cities and ships. Currents carried some far out and down. People examined the deep rocks while particles that were no meal for the family passed between the branches. An orange-red stripe ran through the middle of a pale relative. It followed the main branch while the base and many side branches stayed pale. Here the family looked as though someone had marked its path from one fork to the next. The polyps did not wait for a signpost. They turned their tentacles towards wherever the water was bringing food.

Even beneath fishing boundaries, the water kept moving. People could redirect nets, but heat and dissolved substances still travelled through the depths. Neighbouring branches of the same family sometimes faced different conditions. One relative stayed pale on the left, while vivid pink covered the right-hand branches. Between them, colourful polyps reached into the same current. From afar, the colony looked like two families joined together. A small fish swam through the middle. What mattered to it was that a hiding place still lay between the different branches.

People had stirred up the seabed outside the reef and left waste behind. Currents carried fine particles towards it. Neighbours still had room between the grey branches, but after each cloud of dirt, the polyps first had to clear themselves. Grey branches stood a little further along in the current. Green strands fluttered above; below, a large blue polyp stretched out its tentacles. Small neighbours still sheltered between the branches. The family had not grown equally strong everywhere. This spot was quiet, but when food passed, several colourful crowns moved together.

Plastic from coasts, ships and lost nets had reached the depths. People brought some back up. Much stayed small and unnoticed in the water, where catching arms had to separate food from inedible foreign objects. Some polyps had grown long catching arms. They reached small prey animals, but something else caught on them too: a piece of plastic. The arm held it fast, but the coral could not eat it. The current tugged at it. A fish swam between the branches. The reef needed food, not rubbish.

Cities grew on land, and people kept burning fuels. The deep sea changed too. Fishing gear damaged some reefs; stirred-up sediment covered others. Where could the next tiny corals attach themselves? Part of the family sheltered between rocks. Other branches held on further out. An almost entirely pale relative grew on a quiet rock. It had a small patch of warm colour at its base. Most branches looked like its ancestors'. When the current flowed through them, many polyps opened. This colony might easily have seemed weak. Yet its life showed in the tentacles reaching for tiny morsels.

A research ship had discovered the pale colonies on the seabed. People then moved the fishing boundary. In the dark water, their polyps needed food rather than sun, and undamaged branches where small fish could find shelter. A pale colony stood on an open piece of reef. Its polyps were small, yet room remained between the branches for guests. A fish approached carefully and swam around the base. Behind it, the water pulled less strongly. It settled there. From outside, it could barely be seen, although the coral itself was almost white.

On land, protected deep-sea areas looked like empty spaces on a map. Below, however, many rocks were inhabited. Research pictures helped people protect pale colonies and their little hiding places from heavy equipment too. The next colony shared its place with a smooth stone. A fish had rested behind it, but a current pushed it out. Now it searched for a route between the branches. A polyp drew in its tentacles when the tail fin brushed it. Then the guest was through, and the little catching arms opened again.

People often looked for striking changes in pictures. They could easily overlook an almost colourless colony. Below, what mattered was whether its polyps caught food and whether nets, mud and heat stayed away. An almost entirely pale relative stood in a quiet hollow. Only one crown had a small yellow-green patch. The current found this modest place too, brushing past every fork. When a tiny creature became caught, a crown of tentacles closed around it. Nobody had to be especially colourful to begin another day in the family reef.

A machine had churned up the seabed near the reef. Afterwards, fine sand travelled on with the water. People had to move their work so that the pale polyps would not disappear beneath a new layer of dust again and again. Sand settled beside a pale relative. At first there were only a few grains; later, a little pile. The next strong flow of water scattered it again. The coral could not know where every grain travelled. Its polyps opened when food arrived and pulled their soft feeding arms in again when something touched them.

In the light of their diving robot, people found an almost white colony with open polyps. Broken pieces lay beside it. Heavy fishing gear had been dragged over the seabed and had damaged part of the slowly grown reef. An almost white colony stood in the family reef. Just as many little polyps lived on its branches as on some colourful relatives. A food animal brushed a feeding arm and was held fast. That was what mattered here. The colony ate and kept growing slowly while, outside in the open water, the fish swam their wide circles.

People had observed how unevenly food sank into the depths. Tiny animals lived above, while others below waited for what arrived. A quiet movement of water could mean a long day of waiting for the colonies. A pale colony grew in a quiet corner of the reef. The water barely moved. A fish hovered before its branches, slowly beating its fins. Then the current began to pull again. Fine particles approached, and the polyps caught them. Waiting was as much a part of their lives as feeding.

On a map, this place had long looked like empty seabed. Only a close camera picture revealed the little colonies. People routed the next pipeline around the rock rather than laying it between its branches. Beside a pale colony, a fish hovered in the water. First it moved left, then right. Behind the branches, it searched for a place where the current carried it along less strongly. At last it found one. The polyps moved above its head. Even without strong colours, this place was full of little changes.

People had kept some fishing gear away, but fine particles and warmer water could still arrive. Every useful current remained important to the quiet family. Enough food had to remain for the small neighbours between the protected rocks. One relative had only delicate peach and pink patches. A small resident sat between the pale branches, briefly lured out by the current. It vanished again when a bigger fish passed. The polyps stayed out. Food had just arrived for them, and every open crown wanted to catch some before the water curved around the next rock.

A new protected area lay far below the shipping routes. Heavy nets were no longer dragged over the seabed there. Even small colonies that had barely shown up in the first camera pictures could keep growing among the rocks. A very pale coral stood between the stones. You had to swim close to see its fine tentacles. When food came past, one caught some. Then another did. A fish swam behind the unassuming body. Here it found the same narrow hiding places as among the family's much more colourful branches.

While searching for lost fishing gear, a research device shone its light between the corals. People removed foreign threads without taking seashells away. Later, the current shifted these natural finds onwards until some forks became clear again. A blue polyp sat far out on a pale branch. The water flowed freely past there. Behind it, a piece of shell was wedged in the fork. When a prawn climbed over it, it slipped to the seabed. The branch was clear again. A small prey animal drifted near, and the tentacles caught it before it could pass on.

While a cable was being laid, machines had churned up the seabed. Fine mud drifted all the way to the reef. Later, people changed the cable route so that no more dirt would land on the sensitive polyps. Behind a rock grew a delicate pink relative. The water flowed past more slowly here. A little grain stayed on a branch until the next movement carried it away again. Meanwhile, the violet polyps had caught food. Outside, things were more unsettled, but for this moment the little colony could feed undisturbed.

People could not restore the open sea's food supply through fishing bans alone. Life high above and deep below remained connected: the food sinking down also depended on how people treated the sea above the reef. On a pale relative, only a few crowns stood out by their colours. One was blue, one orange, and a green polyp sat further up. The rest stretched their tentacles into the water too. When food came, they all reached for it. A fish might easily have overlooked the colourful group, but every small meal mattered to the family.

People had drilled for oil on the slope beside the reef. Machines and equipment could disturb the seabed. The pale colony needed distance from such work and a firm place for its yellow base. The base of an almost white colony was yellow. A snail crawled past it and disappeared behind a stone. Above, a polyp caught food. Then a long time passed before the water brought something suitable again. The coral stayed firmly in place. It could not follow the snail, even when everything around it moved on.

People used a diving robot to search for living corals on the dark seabed. Pale polyps opened in front of its lamp. Nearby lay a lost line that a gripping arm was to remove carefully from the reef. The current slipped past an almost white coral. A little blue showed on a lower twig, with a hint of yellow above. Small polyps stretched into the water. They did not need bright colours for their feeding arms to hold on to food. Nearby, a larger fish swam past without touching the pale colony.

Fishing gear spared some deep rocks. Places remained there for larvae and their neighbours. People could improve that protection, but cool water and food had to come from elsewhere; a pretty pastel shade promised neither. A delicate mint-coloured relative grew in a cool spot. Its crowns were pink, yellow and pale blue. A tiny shrimp settled at the base and soon vanished behind a branch. Today the current stayed gentle and brought food regularly. The polyps could remain open. For now, this corner of the family needed nothing more for a good day.

Fishing lines had been left among the deep rocks. People slowly guided a gripping arm past the pink trunk to recover them. A line must not simply be yanked out if coral branches were caught on it. Pink lines ran across the middle of a pale coral. A little fish stopped below them. For a long time, only its fins moved. Then it snapped at something in the water and disappeared behind a rock. Feeding arms closed on the coral too. For a moment, visitor and polyps had found a meal at the same time.

While building a pipeline, people had exposed fine sand. Later, they chose a different route, but the old track remained. Seashells gathered in its little grooves, and animals searched for new hiding places among them. A coral was pink near the seabed and pale at the top. A crab tried to turn over a seashell in the shelter of its trunk. It only managed when it pushed from the other side. Then it withdrew beneath it. Above its new roof, the polyps reached into the water and waited for food.

People sent cameras down and noticed the two colourful crowns first. The uncoloured polyps beside them belonged to the living reef just as much. All needed food; dangerous particles from the human world reached colourful and pale places alike. At its top right, a pale relative had two striking crowns. One was blue, the other violet. Yet when the current came, the plain polyps between them opened too. A tiny prey animal brushed against a pale tentacle. The whole family lived on such small catches. The two colourful crowns looked special, but the others were just as hungry.

A research ship searched for small corals among the deep-sea rocks. Under the lamps, pale tissue was easily mistaken for bare skeleton. So people looked for a long time before deciding a place was uninhabited. A pale coral stood on light-coloured ground. A fish swam so close that it almost brushed against it. Only the delicately coloured polyps made it turn aside. Behind the branches, it discovered an open passage. It squeezed through and stayed sheltered by the reef for a while, until the larger fish had moved on.

Heavy fishing gear dragged over a neighbouring stretch of seabed. The dust it stirred up was carried onwards by the water. Among the pale branches, the polyps had to be able to tell food apart from all the unfamiliar grains. The less noticeable relatives had visitors too. A little fish brushed so close to a pale colony that one polyp drew back. Pink lines ran across its body. The fish disappeared behind the next rock. Soon the polyp stretched out its feeding arms again. The current had already brought the next meal.

After work on the seabed, fine mud had drifted past the reef. People stopped the machines nearby. This gave the little colony no new ability, but its polyps were no longer covered with dirt again and again. In a sheltered place grew a pale relative with a delicate green side branch. Pink polyps were scattered across its body. When the current eased, all was quiet among the twigs. A little snail stayed clinging to the base. Only much later did it crawl on, while above, food was already drifting past the feeding arms again.

On land, children watched pictures from great depths. Cameras had found the reef beneath ships and fishing grounds. The children learnt that animals lived beyond the dark water, in homes that human decisions could reach. One day, a child saw pictures of the coral family. At first, the child looked only for the fish. Then the many little animals on the branches came into view. The child smiled and gave a thumbs-up. Down in the sea, the pale colony knew nothing about it. It opened its polyps while someone above had begun to look more closely.

People used cameras to look for surviving parts of the reef. On the dark seabed, the fine green patches only showed in lamplight. Colour alone said little; open polyps and arriving food revealed more about the family's daily life. Only a few fine green patches set one relative apart from its pale ancestors. Anyone swimming past quickly could easily miss it. The current did not. It brushed through every fork, bringing tiny animals. A polyp caught one. Then all was quiet again until the next movement of water began at the reef's edge.

On long journeys, the research cameras kept returning to the same reef remains. People now kept their gripping arms further from living branches. Smaller guests still moved carefully among the polyps. A red, a yellow and a blue polyp sat on a pale body. A little prawn crawled along the base. When it touched the blue polyp, the polyp withdrew. The prawn paused briefly, then moved on. A little later, the polyp opened again. For the colony, a touch was different from food drifting past.

Above, children learnt that fishing gear and rubbish could reach even deep reefs. They asked the grown-ups for protection. Below, the polyps stayed rooted while people decided the routes of their ships and machines. Up by the sea, children asked why so many reefs were disappearing. They wanted the grown-ups to listen. Below stood a colony with large pink polyps. It could not shout or send a letter. It needed clear water, food and somewhere to grow. The children decided not to forget their questions again.

Children on land learnt that even tiny pieces of rubbish could reach great depths. They wanted to help the reef and thought about having a party. Down below, the water first needed to stay free of any new rubbish from them. One child wished for a party for the corals. Colourful flakes would dance through the water. Then the child thought of all the rubbish in the sea. The party needed no more of it. Below, small food animals drifted around a colony with pink and yellow polyps. The polyps reached out and caught them. For these residents, having enough to eat was a good reason to celebrate.

People had protected some reef remnants. Fishing stayed away, but water from other areas kept flowing through. The family could accept its meal when it came; protecting one rock did not end every danger in the sea. A few green patches dotted the next relative's pale branches. Blue crowns stood out between them. A small neighbour stayed at the base for a long time, leaving only when the current strengthened. The polyps opened. Their home was modest, but today food passed regularly. For one peaceful day, the family could simply get on with its work.

Warming had changed the movement of the water in this part of the sea. On some days, food passed the reef less often. People lowered measuring instruments and looked for the causes of the longer waits. A light blue colony carried pink polyps right out to its outermost branches. When the water flowed more strongly, tiny food animals were carried past. Some escaped; others were caught by feeding arms. The good feeding did not last long. Then the movement eased. The polyps kept waiting while a fish swam over the blue trunk.

People had touched the seabed with fishing gear and stirred up dust. It settled among the dotted branches. Later, the fishing routes were moved away from the reef so that more and more dirt would not keep arriving. Orange dots were scattered across the upper branches of a pale colony. Further down sat dark polyps. A grain of sand was carried against the trunk. The next movement of water lifted it away again. Above and below, the little animals searched for food. Their colours did not reveal which polyp would catch something first.

People had churned up the seabed beside the reef while laying a cable. Fine particles later drifted through the dark water. The colony needed freely flowing water with food, rather than endless new clouds of dirt. Blue water flowed behind the pale branches. Orange polyps sat on the trunk and twigs of another relative. A little visitor approached, turned and moved on. Beneath the colony, the seabed stayed quiet. Above, a polyp caught food. Then they all waited again until the sea brought something new to their home.

A trawl net had torn up the seabed far away. The cloud of fine mud travelled with the water all the way to the family reef. Between the rocks, the polyps had to wait until more food than sand came past again. A pale coral stood in the fine sandy haze. A blue polyp sat at a fork in its branches. A small crab stopped in front of it. Then it saw the pale tentacles moving too. It had overlooked them at first. The current brought food, and the little animals began to feed all over the body.

People wanted to recognise surviving colonies on camera. Pink patches helped them find the same place again. Meanwhile, the next flow of food mattered to the family; a human name or a coloured patch did not make the dark habitat safe. Two pink patches stood out on a pale relative: a small crown above and a low side branch. The current reached them by different routes. Above it arrived directly; below it first curved around the trunk. The polyps there waited longer. At last they opened too, and the same quiet search for a meal began between the different branches.

A camera returned to a protected patch of seabed. Since heavy nets had been banned, no new branches had broken. People now also searched among the stones for the smallest pale colonies. Almost entirely pale corals belonged to the family too. One had a yellow patch near its base. There, a little animal settled on the stone and cleaned its feelers. Above it, the polyps stood in the water. Their quiet movements revealed that many animals lived together in this unassuming place.

After heavy fishing gear was banned, a small rock stayed untouched for a long time. On later visits, people saw new branches there. No machine had built them. Over years, many little polyps had enlarged their shared body. A delicate pink colony grew in a calm place. Its branches were still small. A tiny animal could hide between them, but no large fish could. Over many years, the colony kept growing. New polyps joined it. Later, larger guests found space too, and the small beginning became a piece of the reef.

People had kept heavy fishing gear out of some deep areas. Small family branches could remain there. Other influences still came with the water: dissolved substances, heat and irregular food reached the quiet rocks within protected boundaries too. A hint of pink ran along a relative's trunk. A closer look revealed the fine movements of its pale polyps. The current passed this rock quietly. It brought little, but today several small particles reached the branches. The family caught what it could and stayed open for the next movement of water.

A research lamp slid over the dark rocky seabed. A larger fish passed between it and the coral. Its shadow disappeared a moment later as the device turned its camera towards the next piece of reef. A green stripe ran through a white body all the way to its base. In the light of a research device, a larger fish swam over the branches. A smaller one immediately disappeared into a rocky crack. When the visitor was gone, it came out again. Soon the circle of lamplight moved on too. In the dark, the polyps kept catching food from the current.

People had surveyed the trawl tracks around the last pieces of reef. They protected bare stones where young corals could gain a hold. But a new colony did not grow big at the press of a button; many currents passed over every beginning. A pale yellow colony grew on a low stone. The current brought more food at some times and less at others. On a quiet day, a larva caught nearby. Later, a new polyp sat there. It could not hide a fish yet. But between it and its large neighbours, a beginning had been made.

Researchers lowered small measuring instruments into the depths. They wanted to know when food reached the reef. Some measurements showed currents full of food, others long pauses. For the little coral animals, this difference mattered every day. Polyps of many colours sat on a pale yellow coral. During a quiet spell, very little food floated past. The little animals caught what they could reach. Then the water grew livelier. Suddenly something was happening on almost every branch, and a passing fish had to go around the outstretched tentacles.

People had kept heavy nets away from an area of steep rocks. Old coral ground remained in its crevices. New branches could grow outwards, where the current reached them more strongly than deep in the sheltered corner. A colony's branches reached out of a crack. Its body was brown below and pale blue above. Small animals lived in the sheltered crevices. The further out the branches grew, the more water flowed past them. A fish waited behind the trunk. It knew the difference between the calm crack and the open current.

People had stopped using heavy seabed equipment here. Rocks and hiding places survived. Cool water and food came from elsewhere; the protected spot gave the mint-green family a chance, but no promise for all time. A mint-green relative grew in a quiet corner. Its crowns were magenta and violet. Today food passed regularly, and most polyps stayed open. A small shrimp wandered beneath the branches. When the current turned, it changed sides. Here the family had found a place where, for now, it could manage without large protective devices.

The researchers checked their maps once more. Some pale colonies had been easy to miss among the stones. They too were places that needed protection from heavy nets so their branches could keep growing. A pale coral had a blue shimmer on just one upper polyp. It was easy to overlook in the water. A fish only spotted it when it was right in front of it. It swam around the branches and found a narrow passage. Calmer water waited behind. Even an unassuming colony could matter to a small visitor.

By now, some people protected individual reef slopes from fishing gear. Elsewhere, fishing and building continued. So the sea offered very different places. Where the current brought enough food, new colonies could grow. Their descendants did not all look alike. A different colour alone did not reveal who coped better. On a pale relative, the large lower polyp was green. Many pale polyps sat above. When a little animal drifted past the trunk, the green one caught it first. Later, others received something too. The colony lived on many little meals like these. None was large, but together they helped its residents keep growing.

While surveying the seabed, researchers had seen how many small animals travelled through the water. People protected the surviving pieces of reef. There, the current could keep bringing food without a new heavy net clearing away the branches. A thin green stripe ran along a pale coral. A small animal caught in the fork beside it. It moved its legs but could go no further. Only the next current freed it from the branch. It drifted away, close past the open polyps. Another little animal was caught by a polyp.

A small patch of reef had remained untouched after the fishing trips ended. Researchers still found living colonies there on later visits. Their new branches did not make up for the old losses, but they continued to offer snug shelter. A pale orange coral stood in a quiet hollow. A bluish polyp sat on a lower branch. A little fish just fitted between its base and the next stone. It stayed there while a larger fish passed outside. When it swam out again, it discovered other gaps in the reef. Some of them were already occupied.

People sent cameras and measuring instruments into the depths. They wanted to understand how their emissions and fishing were changing the habitat. While they watched the pictures above, the polyps below waited for food. Another colony looked a little different from every side. Blue lay below, turquoise in the middle and delicate orange on one twig. A fish swam a circle around it. Then it moved on to a rock. The coral stood still and caught food long after its swift visitor had disappeared.

People had marked small pieces of reef on their new maps too. They wanted to stop a later machine from overlooking them. Their colours became visible under the lamps; the narrow spaces between their living branches remained more important. A colony wore so many colours that a little fish only noticed the narrow passage on its second look. It swam between two branches and stopped behind them. The water pulled more slowly there. When it came out again, an even smaller fish followed it. Now two inhabitants knew this quiet place in the colourful reef.

A ship had carried out work on the seabed near the reef. Afterwards, fine dirt had arrived with the current. People moved their equipment further away so that less extra dust would drift among the colourful branches again. Above the dark seabed stood a turquoise-green relative with red and yellow polyps. Fine lines extended from some dark branch tips. A little fish passed close above them. Below lay a stone behind which a tiny resident disappeared. The current swept over both and brought food to the feeding arms that had stayed open.

People sent lamps and cameras down to deep rocks. Their light revealed the family's colours. The polyps did not need that light to feed; water still had to bring their food from the darkness. A diving lamp revealed a lime-green relative between dark rocks. Its branches bore crowns in many vivid colours. Tiny neighbours had found homes here too. The family had to get along with them. That was easier when the current brought enough food. If the water turned bad, even the loveliest community could not simply make the difficulties disappear.

Fishing lines had been left on the seabed. One hung near the red branch tip. People guided a gripping arm carefully past it, because a sudden movement could have broken the slowly grown coral. On the side of a pale colony, a small branch tip was coloured red-orange. A polyp below it was catching food. A fish darted past so quickly that its feeding arms curled in for a moment. Then everything was quiet again. The polyp opened once more, and the water slipped between the red branch and its pale neighbours.

In the lamplight, people discovered a green branch on a pale coral. They watched its polyps feeding. Then they searched for lost fishing lines that had become tangled in the reef. The family also had almost white relatives. On one, only the upper left branch was a little green. A small polyp below it held its feeding arms in the water. It caught something, drew itself in and opened again later. The pale colony went about its daily life just like its brightly coloured neighbours.

A diving robot lit up the yellow branch of a pale colony. A lost line had become caught beside it. People slowly guided a gripping arm towards it so that no more twigs would break from the trunk during the recovery. Right at the top of a pale relative, one branch was yellow. The others stayed white. A small crustacean drifted past the yellow twig, turned aside and reached a polyp lower down. There it was caught. For the coral, every one of its little residents mattered, even in the less noticeable parts of its body.

People brought cameras and measuring instruments to the pale pink coral. They wanted to see how much food arrived and whether the seabed remained undamaged. Their work was meant to help without leaving new marks among the slowly growing branches. Beside a rock grew a pale pink relative with violet polyps. A little animal settled on the seabed beneath it and stayed there for a long time. Above, the wait was not quite so quiet. First one polyp caught something, then a second. The colony kept growing slowly, while below, the little visitor eventually swam away again.

Fishing boats travelled to new grounds above the deep reef. Below, tiny food particles still reached the rock regularly. People could barely see these meals; in pictures, the colony's vivid green stood out first. A bright green relative stood above the rock. Its orange crowns opened whenever food passed. A small fish thought it a good hiding place and slipped behind the trunk. When it emerged, a tiny eddy remained. Several polyps reached into it. In the large family, even little movements like these could be an event.

A research ship returned to the same rocks. People compared new pictures with old ones and counted small polyps too. Beneath them, the current flowed unevenly past; some prey animals only reached a branch by a roundabout route. A polyp with blue and yellow tentacles sat on an almost white coral. A food animal drifted close in front of it. It seemed to have gone when a small swirl brought it back. This time, the polyp caught it. Higher up, a pale neighbour caught some food. Not everyone in the reef received something at the same time.

People used small devices to search for rubbish among the rocks. They took away foreign plastic, but left natural stones in place. Small animals kept hunting for food among them, while the polyps waited for prey to drift near. An orange patch sat on a lower branch. A prawn crawled past it and stopped behind the pale trunk. Above it, the polyps reached into the current. When a prey animal passed, fine tentacles closed around it. The prawn kept searching on the seabed. What was a mouthful for the coral was barely visible to it.

People planned to extend a fishing area right up to the deep reef. Pictures showed many little colonies there. The pale relative with the colourful base was one of them; its fixed home was to remain untouched. On an almost white colony, only the base was brightly coloured. Violet, green and red lay close together. Above, pale polyps stretched out their feeding arms. A larva landed on a stone very close by. It stayed there as the current flowed on. In time, the little animal grew into another relative.

People had carefully lifted an old net from a reef remnant. Afterwards, there was more room among the surviving branches again. Small fish could swim through, but the missing branches would not immediately grow back because of it. A few orange polyps sat on a pale coral. A little fish came from one stone to the next and stopped before the branches. It fitted through a narrow passage. A second fish waited behind. For a moment, both stayed still. Then they swam out on different sides and left the place free again.

People filmed surviving reef branches while equipment damaged the seabed elsewhere. In lamplight, this relative appeared sea green and violet. Beside the protected place, new clouds of sediment rose and spread slowly through the dark cracks. A sea-green relative grew at the family reef's edge. A violet crown in the middle of its body stood out in lamplight. Below, a little animal darted around a side branch. The polyps opened as the water's movement grew stronger. They were in no hurry to explain their colour. A meal was passing, and that mattered more just now.

A ship studied the deep reef with cameras and measuring instruments. People wanted to know how their emissions and fishing were changing the habitat. Meanwhile, among the pale branches, a polyp caught the next little meal. A red polyp sat higher up, with a blue one a little below. The rest were pale. When food passed, an unassuming polyp on the right caught something first. The red and blue ones kept waiting. Colours did not decide who ate their fill first. That also depended on which route the little animals took with the water.

A ship lowered measuring instruments over the reef. People wanted to know when the current brought food among the lower branches. The warming of the Earth had changed the sea, and hungry polyps could not leave their places. On another colony, the blue polyps sat lower down. Above, the branches had stayed pale. A little fish swam slowly around the trunk, then darted away. Behind it, the water kept moving for a moment. The coral kept waiting. Soon afterwards, fresh food arrived from the open sea.

People had protected the seabed by this rock. But the water remained changed by earlier emissions. New corals needed firm, bare places and time to build their small coral skeletons there. At the red base of a pale coral, a larva caught beside a stone. It was tiny and found just enough of a hold. As the current flowed over it, it began to settle firmly. The large colony above it had been there a long time. Now it was gaining a neighbour much smaller even than its smallest branch.

While collecting an old net, people worked slowly with a small gripping arm. They did not want to tear away living branches with it. Afterwards, there was more room for water and small visitors among the surviving branches again. Two red polyps stood out on a pale colony. A little fish stopped before the lower one. Behind it lay a fork through which it could just fit. It slipped inside. Above it, the polyps caught food. When the current turned, it did not have to leave. There was a quiet place on both sides behind the trunk.

The researchers learnt to count the unassuming colonies too. On every visit, their cameras briefly shone between the stones. This meant pale animals were no longer overlooked simply because they were less eye-catching. A deep blue polyp sat in the middle of a pale branch. Further up were an orange one and a yellow one. A small crab crawled underneath as the current began. Above it, the pale tentacles opened too. The coral held more living neighbours within it than the crab could see at first glance.

People used the sea for fishing and transport. Yet some deep rocks still held places for the family. Where the current came in short surges, polyps had to catch their meals between long pauses. Peach-coloured branches stood near a crack in the rock. Their crowns were blue, red, green and yellow. Today the current came in short surges. Each time, the polyps opened, reached for food and waited again. A small neighbour held on behind the trunk. Between two surges, it became so still that even the loose trail of sand at the base stayed put.

When people lifted an old knot of netting from the reef, natural seashells stayed on the seabed. Later, little animals kept pushing and turning them. Between corals and stones, they made tiny new places that no human had built. Some polyps on a pale coral were pink. A piece of shell lay beneath the lowest one. A little crab carefully pushed it across the seabed until it leant against a stone. Now it had a roof. Above it, the tentacles moved in the open water. In the reef, many little things kept creating new places to live.

People discovered the coral's yellow and dark patches in the lamplight. Broken branches lay beside it. Heavy fishing gear had touched the seabed; now a new protected boundary was to prevent more colonies from breaking. A yellow branch reached upwards above a relative's dark base. Other twigs had stayed pale. On one side, a dark polyp sat beside an orange one. When food passed, their feeding arms moved. Some was caught; some drifted onwards. The current connected this colony with the neighbours beyond the next rock.

People had set a new boundary for fishing gear in front of a reef remnant. Behind it, bare firm stones remained. Larvae could gain a hold there, as long as no heavy machine buried the little beginning beneath loose ground again. Yellow ran through the middle of a pale body. Pink and blue polyps sat beside it. When a larva found a hold on a bare stone, it was barely visible. The big branches above it slowed the water a little. Here a new part of the family began, small enough to disappear beneath a seashell.

Nearby, a heavy net had torn up the seabed. People marked the undamaged places on a map. No fishing gear was to be dragged through them again, so that more descendants could find a firm place to settle. A light blue descendant had grown between two stones. Its polyps were only delicately coloured. A little larva landed on the rock beside it, came loose again and was carried onwards. The older colony stayed firmly in place. Slowly, it formed new polyps on its twigs, while more and more animals arrived and moved on around it.

A cable was to be laid past the reef. Only the pictures from a diving robot showed the people how many corals stood there. They changed the planned route so that the slow-growing branches could survive. Further into the reef, things became more colourful again. Yellow stretched across the middle of one colony, and orange lay along a branch. The base stayed pale. A larva drifted between the twigs. It let the water carry it onwards until a patch of bare rock lay ahead. Perhaps it would grow into a new coral there.

Above, coasts were built up and more ships set sail. Below, their traces arrived as fine particles and distant noise. Yet the current still brought food to differently coloured family branches on this rock. In a quiet hollow, a colony shimmered blue and violet. It turned yellow at the tips; some polyps had several colours. A shrimp studied one crown, then another. ‘What's your favourite colour?’ The current did not wait for an answer. It brought a helping of food, and at once every polyp was busy.

People measured changes in the sea over many years. The water did not warm equally everywhere, and food arrived along different routes. This delicately coloured relative also needed good conditions in its fixed place. On another relative, the yellow began on the lower trunk. Above, only little pink dots lay among pale branches. A polyp had just caught some prey. It drew in its feeding arms while the others were still waiting. The reef did not all eat its fill at once. For each little animal, the next meal came at a different time.

Over decades, human emissions had warmed the water. The routes and amounts of food changed at the deep reef. People lowered measuring instruments among the rocks and watched when the polyps received food. The pink polyps of a pale relative stood far apart. Even so, they all belonged together. When food passed, some caught something straight away and others only later. A tiny creature escaped between two feeding arms. The next polyp caught it. So on this patch of reef too, a little meal came from the passing water.

While building on the seabed, people had stirred up a great deal of sand. Some settled near the protected rocks. Now even a small fish's movement could carry grains among the polyps again. A green branch reached out of a pale colony. Two red polyps sat on it. A fish swam beneath the fork and stirred up a grain of sand. It briefly caught on a tentacle tip. Then it fell to the seabed. Straight afterwards, something edible came with the current, and the little animals caught food again.

People kept a small area free of nets and heavy pipelines. On later visits, they saw more branches than before. The protected place remained in darkness; its colonies grew on the food they caught. A delicate pink coral grew on a quiet stone. At first, its branches were narrow. Over many years, new little animals joined it. A seashell that had once lain beside the base gradually disappeared among the forks. When a crab searched for it, it found a new hiding place in the growing reef instead.

Cars, ships and power stations had released a lot of carbon dioxide for a long time. Some of it entered the sea and changed the water. This made it harder for the corals to build their solid calcium carbonate branches. Four red polyps sat on a pale coral. When food came with the water, they stretched out their feeding arms. The other polyps belonged to their colony just as much, even if they were not red. A tiny creature was caught. Then the water flowed on towards the next branch of the big family.

People watched the family on camera over many generations. Its colours changed while the deep sea stayed dark. Changes that barely showed in pictures mattered too: food, temperature and substances in the passing water. A relative wore its colours in one long, gentle transition. From pink tips, they passed through blue and green to a yellow base. A small neighbour climbed along the route and vanished behind a fork. The polyps stayed in place. When the current came, every crown moved, from the highest pale twig to the lowest colourful branch.

In some places, people reduced their emissions, but the sea changed only slowly. Water samples from the seabed still showed the old traces. So one protected rock alone could not solve every difficulty the colonies faced. A pale green colony had a reddish polyp near its base. There, a crab carrying a seashell crawled past the branches. Its house caught in a narrow spot. It backed away, turned and tried the other side. This time it fitted. Behind it, the tentacles moved freely in the water again.

During surveys, people had taken sediment samples beside the corals. They found fine deposits from different times. The colony drew no food from them through roots; its polyps caught small animals from the passing water. A yellow stripe ran lengthways through a pale coral. Small prey animals passed between its branches. Some were caught; others drifted on to a neighbouring colony. The current linked the places in the reef without stopping anywhere. On the seabed, a crab crawled a little way against it, then disappeared beneath a seashell.

People studied how food travelled down through many layers of water. If something changed higher up in the sea, the meal on the seabed could change too. The corals could not grow their own food and still depended on the current. Many blue polyps sat on a pale coral. When small prey animals drifted towards them, tentacles began moving everywhere. Some caught something; others had to wait. Beneath the trunk, a fish stayed in the calmer water. It remained until the strongest flow had passed. Then it swam on, leaving the little animals to their meal.

Researchers sometimes found remains from land and coast on the deep seabed. A leaf could cross many layers of water before coming to rest among rocks. No tree or garden seeking light grew from it down below. The water took winding paths around a pale coral. A little leaf first turned around an upper branch, then sank and was pulled upwards again. A fish followed it with its eyes. At last it drifted away. Tiny food animals took its place. The colony's fine tentacles were already stretched out.

Over many years, carbon dioxide from human emissions entered the sea. This changed the water and made it harder to build their calcium carbonate skeletons. So the yellow and pink relative still needed food for its slow growth. One relative was yellow on one side and pink on the other. Its base was dark. As the water flowed through its branches, it reached both sides. Here one polyp caught something, there another did. All belonged to the same colony. A little fish circled the trunk and found new gaps to swim through on each side.

People could see the different coloured patches by their cameras' lights. Between visits, the reef stayed dark. Ships worked above, and currents repeatedly carried fine particles from nearby seabed areas into the family's habitat. Blue lay at the top left, green on the right, turquoise below. Red crowns sat between them, and dark edges separated some patches. A small shrimp crossed every colour and vanished behind the trunk. The relative stayed on its rock. When the current came, its polyps moved together. No coloured patch could completely block the water's path to the next branch.

People collected ever longer series of measurements from the deep seabed. Temperature and food changed over time there too. Between visits, the colonies had to make do with the water that reached their fixed spot. A thread caught on a silvery-blue branch. It swayed back and forth in front of a yellowish polyp. The next current pulled it further until it came loose. Behind it, fine tentacles opened. A small prey animal caught on them. However unassuming the body looked, the life inside it needed food every day.

In this future, there was a lot of fishing above the reef. Lost lines sank to the seabed and caught among the branches. People searched for them with diving robots so that their equipment would not injure even more animals. Pink polyps sat beside blue, green and yellow ones on a pale colony. The water first slipped past the right-hand side. There, the little animals caught food. When it turned, it was the other branches' turn. The coral needed its many feeding arms, because not every twig received the same amount.

Researchers compared the food in the current with what lived in the sea above. The deep-sea corals' food travelled a long way. So people also had to care for the sea beyond the visible reef. Pink polyps sat on a yellow coral. When a little fish swam too close, they drew in their tentacles. It stopped behind the trunk and stayed still. After a while, the little animals opened again. The next food came from the other side, and the fish had to shift its quiet hiding place a little.

During another survey, people found tiny new corals on protected stones. Heavy equipment was no longer allowed to touch this seabed. Even so, the little colonies needed many years before larger animals could fit between their branches. A delicate yellow and pink coral grew beside a dark stone. A larva caught in a crack at its base. There was still room there. After a while, a tiny new polyp sat in the reef. It was much smaller than its neighbours. Yet even the biggest branches had once begun like this.

People watched dark and colourful polyps with the same camera. Some were eating; others waited. On the ship, people compared their pictures with measurements, because their actions had changed the water and seabed. Among the colourful polyps of a pale colony sat some very dark ones too. They belonged just as much as the blue and yellow ones. When food passed, several little animals caught something. Another caught nothing and kept waiting. The sea did not share its meals out evenly. In the family reef, patience was part of everyday life.

People watched the family on camera over many generations. Colourful descendants grew on different rocks while fishing and shipping continued around them. Between visits, unwanted cargo also reached the dark seabed and stayed there. A relative wore pink and red above, orange in the middle, and blue, violet and green below. The colours lay close together like pieces of a quilt. Yet room for water remained between the branches. A small fish glided through a gap. The polyps caught food from its wake while it was already vanishing beyond the colourful body.

An undersea cable now lay far beside the reef. People had changed its route after discovering the corals. The old colonies could stay on their rocks while generations of little neighbours changed around them. Dark stripes ran across the pale trunk. A small animal crawled along it, stopped before a polyp and took another route. The coral had been in its place for a long time. Around it, stones had shifted, mussels had settled and fish had hidden. The reef never stayed quite the same, even though it grew slowly.

People had discovered a lost line lying near the violet twigs. A diving robot was to retrieve it. The gripping arm moved slowly so that helping would not break off more branches and send them to the seabed. Violet lines ran over the pale body of a relative. A little fish looked briefly between its twigs, then moved on. The polyps were still open. When food arrived, some feeding arms closed. A tiny animal escaped and was carried to the next colony. In this way, the same current connected many members of the big family.

With cameras, people kept discovering new corals in the darkness. At the same time, they were changing the sea through emissions and fishing. So some protected whole reef sections from bottom nets, allowing the colonies to keep their fixed homes. Polyps in many colours sat on a pale relative. A yellow one was small; an orange one was bigger. Further right, a blue one opened. They were all waiting for food. When a little rush of water flowed through the branches, several feeding arms caught something. Afterwards, there was time to wait again while a fish slowly moved on above them.

People collected samples beside a damaged piece of reef and took loose rubbish away. They left the old seashells in place. Small inhabitants found shelter among natural edges like these, even where tall coral branches were still missing. Yellow polyps sat on a very pale trunk. A little fish nudged an old seashell on the seabed with its nose. It tipped over and revealed a narrow gap. At once, the fish disappeared inside. Above, the colony caught food. The reef was made of many such places, each of which suited someone.

In time, warming caused by human emissions also reached deeper waters. People searched for reef sites that were still suitable. There, they had to keep heavy fishing gear away so that the family's descendants could grow safely. A light blue colony carried yellow and green polyps. The big one on the lower trunk had just caught some prey. Further up, smaller ones still waited for food. A fish swam past in a wide arc. Then the current turned. Now little animals reached the higher branches too, and more feeding arms closed.

People sought new fishing grounds far offshore too. Beneath their ships, some deep rocks remained untouched. Food particles still reached open polyps here, while nearby equipment worked on the seabed and fresh clouds of particles rose. In a diving lamp's light, the next relative appeared bright orange. Its green crowns looked like little flowers, but they were hungry animals. A fish approached, startled at a movement and darted away again. The polyps caught tiny particles. On this deep rock, the family had found food, and while the current lasted, many crowns stayed open.

Above the dark seabed, the current carried food to the orange polyps. People measured this flow because emissions were changing the sea. With their pictures, they searched for places that remained suitable for the family. A pale relative with orange polyps grew above yellowish ground. A small crustacean moved past its base. Above, a polyp stretched out its feeding arms, but the crustacean stayed out of reach. It climbed behind a stone. The coral kept waiting. The next flow of water brought much smaller prey to its branches.

Where people had once dragged heavy nets, the large colonies stood far apart. Small fish had to swim longer over open ground. So every surviving fork could matter on the way to the next piece of reef. Blue, red, green and dark polyps sat on a pale orange coral. From the front, only some could be seen. Only when a fish swam around the trunk did the others appear. The colony reached further than it had thought. Behind the last fork, it found a calm place and stayed until the water pulled less strongly.

A research ship studied how food reached the reef around large stones. Its devices stood beside the colonies. Among them, the polyps occupied very different spots, although they belonged to the same connected body. A dark polyp sat on an upper branch, with blue and yellow patches below. The water turned around a stone and reached the branches from behind. A tiny prey animal caught on the tentacles. Food arrived further down only later. The little animals shared the same body, yet each had its own place.

People studied the pale branches with cameras and watched the red polyps feeding. Lost lines lay nearby. They had to be removed without breaking off more coral twigs during the recovery. Red polyps sat on pale branches. When water slipped past them, their feeding arms opened. A small crustacean was caught; another drifted on out of reach. The colour of the branches did not say whether an animal was hungry. There was life in this colony: it ate, grew slowly and belonged to the big family.

People used lamps and cameras to examine which colonies had survived their interference. A vivid red was easy to spot. They also had to measure and observe whether enough food arrived and what the water contained. A red relative stood beside the dark stones. Its crowns wore blue, yellow, green and violet. A small fish curved around its main branch, then paused in open water. The current came from ahead. Several polyps stretched their tentacles and caught what they could reach. Soon the fish moved on, leaving the red family on its rock behind.

People had set small traps to collect sinking food. Later, they lifted the containers back up. No one brought the corals full plates; they still depended on the changing meals of the open sea. This coral's highest tips were purple. Below them, pale polyps opened in the current. A small animal drifted past from the side, was pulled around the trunk by the water and reached a lower branch. There was something to eat down below too. For a large colony, every branch washed by plenty of water mattered.

At the edge of a work area, machines had loosened the seabed. Small heaps of sand moved on with the currents. People above might have finished long ago while the particles they had stirred up were still arriving among the branches below. Blue, red and green polyps sat on a pale colony. A fine strip of sand travelled across the seabed. A little heap stayed at the base, then grew smaller again with the next current. Above the sand, the branches stood clear. There the polyps could stretch out their tentacles and reach for small prey animals.

The research cameras showed people open fishing tracks beside surviving rocks. They wanted to allow no new damage there. The remaining branches offered little animals calmer places while water flowed freely over the highest tips. A coral's body was orange above and pale below. A little fish swam from its base to the highest branches. The water pulled harder there. It turned back and sought shelter in a lower fork. Above it, the polyps caught food. Every place in the reef felt different to a small swimmer.

Lost fishing gear had become caught in some of the reef's twigs. So people limited fishing there and carefully cleared it away. Small animals could still swim and find food among the surviving pink branches. One pink relative had blue polyps. Little animals darted through the surrounding water. One paused briefly between two branches before moving on again. The colony did not move along with it. It stayed on its rock and stretched out its many feeding arms. It did not have to swim after anyone through the sea for its food.

Through emissions and fishing, people were changing living conditions in the sea. So a diving robot watched this light blue relative too. On the ship, people searched for ways to keep their work away from the sensitive branches. A light blue relative carried green, orange, pink and blue polyps. A little fish came so close that one briefly drew back. The others stayed open. When the visitor had swum on, this polyp stretched out its feeding arms again too. Soon afterwards, it caught a tiny creature that arrived with the water.

People collected samples of the water flowing past the family reef. The small food animals arrived unevenly. While people above argued about protected areas, the polyps below had to get through the quiet spells too. A pale blue colony grew beside a low rock. Its pink polyps reached the water above. On some days, plenty of food drifted past; on others, little did. So the reef did not grow bigger every day. A small crab that had found a hiding place here only noticed new branches after a long time.

People compared protected colonies with reef areas still being fished. The simple red relative needed no equipment on its branches for that. Yet whether its home stayed suitable still depended on disturbance nearby and the arriving currents. A burgundy relative stood on a plain rock. No umbrellas, walls or devices surrounded its branches. Its red and magenta crowns waited for food. When the current began, the fine tentacles bent the same way. A small neighbour slipped beneath the lowest branch. Even a simple place could meet the family's needs for a while.

Far above the dark reef, tiny animals and algae lived in daylight. What happened there also affected the food below. Warming caused by human emissions changed these meals on their long journey. A violet polyp opened on a yellow branch. A small crustacean floated close by and disappeared in one swift grasp. Further down, a second polyp caught food too. This happened many times a day on this coral: waiting, feeling, catching. The family did not need big teeth for that.

On land, people continued burning coal, oil and gas. This warmed the sea too. Even in the depths, temperatures slowly changed, while the coral had to keep catching food in its fixed place. Another colony was orange-brown below and almost white on its upper branches. Colourful polyps sat between the two areas. A larva drifted past them and landed on a stone. It stayed there. While the older coral caught food, the story of a new relative was already beginning beside its base.

A machine had broken up the seabed elsewhere. The fine particles did not stay beside its track, but were carried further away. When the cloud reached the reef, there was suddenly more mud than food between the polyps. Fine sand moved through the water around a pale coral. Some polyps closed when grains landed on them. The next current pushed the sand onwards. Only gradually did the little animals open again. They needed clear water at their tentacles. Food was welcome; a blanket of sand was not.

While ships sailed above and power stations released emissions, the pink coral carried on living in darkness. Its yellow polyps caught food from the water. They needed no light for that, but they still needed good water conditions. Yellow polyps sat on pink branches, little ones beside big ones. A tiny crustacean drifted between them. Twice it escaped; then feeding arms held it fast. For the coral, this was a good meal. A fish came past and searched for food too. The sea fed hungry animals, large and small, in very different ways.

People lowered cameras and measuring instruments all the way to the deep coral. They wanted to see how water and food reached its branches. Their emissions and their work on the seabed had changed the habitat over many years. On one relative, the colours blended gently into one another. Pink lay beside yellow, blue beside a light green branch. A little food animal was carried close past the trunk. A polyp held it fast. Further up, others were still waiting. For the colony, its slow continued growth came from many little meals in many places.

People studied the traces their waste and seabed work left in deep water. Lamps revealed the branches; small instruments tested the water. Meanwhile, the family waited for the next flow of food from the dark surroundings. A grey and brown relative stood among the stones. Only its crowns bore little green, orange and pink patches. A fish passed close without stopping. Just afterwards, a fine stream of food reached the branches. The polyps moved together despite looking different. Colour did not matter for this meal; each had to catch its own prey.

People watched the colourful polyps in the glow of their robot lamps. Some caught food; others waited. Because people were changing the sea through emissions and fishing, they now also had to study the routes of this food more closely. One relative had so many colourful polyps that a little fish swam round its trunk twice. Yellow sat beside violet, blue beside red. Then the fish moved on. The polyps stayed open. Beneath it, one was just catching a tiny crustacean. The coral did not have to show anyone how colourful it was to get a meal.

Fish were caught above the reef, and fewer and fewer undamaged hiding places remained on the seabed. Little visitors crowded among the surviving branches. Not every gap was wide enough when a bigger fish came past. Yellow, blue and pink sections lay close together on one coral. A little fish swam up beside it and disappeared behind the highest fork. A second waited below. When the first reappeared, both raced through the narrow passage. The polyps briefly drew in their tentacles, then opened them again.

With a lamp, people watched the colourful branch tips. They wanted to see when food arrived. Their fishing and emissions had changed the habitat; now they had to take better care of the deep reef. A pale relative carried colour mainly at the ends of its twigs. Blue, green and pink polyps sat there. A fish almost brushed a branch and turned aside in time. Soon afterwards, it swam back more slowly. Between the colourful tips, it found a gap. The colony remained untouched and kept catching food from the water.

Work on a cable had stirred up a lot of fine mud. People moved the next work site further away. This gave the red polyps no extra food, but less added dirt drifted among their branches. Red polyps sat on another relative's pale pink branches. A little fish stopped in front, looked and moved on. Behind it, food arrived with the water. One polyp caught something; the next was still waiting. Much in the reef happened so quietly that a passing visitor would hardly have noticed it.

A research device travelled slowly over the rocks and shone its lamps on the branches. Their colours became visible only in this light. Behind the device, the depths stayed as dark as before. The light of a research device swept over a coral. A blue section ran through its middle, with pink polyps beside it. The circle of lamplight moved on and left the branches in darkness again. The little animals still caught food. What mattered to them was what the current brought, even after the device had reached the next rock.

Human machines reached the dark rocks with lamps. Only their light made the colourful crowns clear. When the devices moved on, the reef stayed dark; the family still felt for food in the current. A brown relative stood between dark rocks. A passing lamp revealed its colourful crowns: blue, red, yellow and violet. When the lamp vanished, the sea stayed dark. Yet the polyps kept catching food. Their family had grown up with the current long before any person brought a light down to its branches.

An unmanned device descended from a research ship. Its lamps revealed the colours of the branches for a short time. When it moved on, the reef stayed in darkness; food still came with the water. A yellow coral stood out among grey stones. The water above it was dark, and its polyps needed no sun to feed. They waited for the current. When small prey animals drifted past, fine tentacles moved everywhere. A tiny fish settled behind the trunk, where the water flowed more slowly.

At the sea's surface, algae lived in daylight. From this upper world, food later reached the depths. Through their emissions, people changed conditions in both places, although the yellow coral itself fed in darkness. A golden yellow relative carried pink polyps on its twigs. When food passed, the little animals stretched far out. A feeding arm touched some prey and held it fast. Right beside it, another little animal escaped. The sea kept bringing new chances. The coral had to wait until something passed close enough to one of its polyps.

A research ship tracked how much food reached the seabed from the upper water layers. The reef needed no sunshine for this. Under the devices' lamps, its colours became briefly visible, then the polyps kept catching food in the dark. A yellow coral stood among the stones. On an upper branch, a polyp caught a little animal. At first, nothing reached the bottom. Then the water turned around the trunk and brought food there too. A crab crawled over the seabed, searching for scraps. The reef offered something to eat in many places.

On land, people kept burning large amounts of coal, oil and gas. The effects did not stay at the surface. Even the water in the depths changed slowly, while the colonies still depended on regular food. A yellow coral had red, blue and dark polyps. As the current passed a stone, it reached the left side first. There, the little animals caught food. A little later, the water turned and the other side received its share. No one had to move. The sea came past all by itself.

On land, people tried to release fewer exhaust fumes into the air. In the deep sea, older changes still had an effect. The colonies still needed food from the water and a seabed that no heavy machinery tore up. A yellow coral stood where the reef left a small gap. A larva drifted over the open ground. It touched a stone, came free again and was carried on. Not every place offered a hold. The yellow colony had been here for a long time. Beneath its branches, a little fish stayed sheltered from the current.

People sent more cameras and lamps down to follow changes in their reef sites. Colourful places became visible. Sunlight never reached here; danger came from damaged habitats and changed water, not sunburn. Dark blue, green and violet patches marked an otherwise pale relative. Large clear spaces remained between them. A lamp glided over the branches, revealing every stroke of colour. Then its light moved to the next rock. The colony stayed behind in dark water, where its polyps felt for the same tiny movements as the other family branches around it.

People used cameras to watch where new colonies settled. Not every larva stayed in the protected area. The current carried many onwards until some found a hold on a firm stone between two old pieces of reef. Yellow, blue and pink sections made a colony colourful. A larva drifted past it. It briefly touched a branch, came free and travelled on with the water. Only on a bare stone did it hold fast. There was still room there for a new polyp. The family spread through many little beginnings rather than through steps.

The seabed had been stirred up while a pipeline was laid. Later, the fine mud settled between the rocks. When the current returned more strongly, it carried some away again. Blue and yellow polyps sat on an orange coral. One day, a fish stirred up the sand at its base. Some sank between the lower branches. The little animals withdrew until the water was clearer again. Then a new current reached the place and carried the fine grains away.

Fishing gear had destroyed some hiding places, while others survived among steep rocks. People kept new nets away. Below, bigger fish searched for food, and smaller ones had to know the narrow forks that remained. A blue branch reached left out of a pale green coral, with a pink branch below it. When a fish came from above, a smaller one darted into the lower fork. It was narrow enough to stop the big one following. It moved on. The polyps had briefly drawn in their tentacles and now opened them again.

Shells and small stones lay loose on an old fishing track. Nets no longer passed that way. But what they had left behind was still pushed along the seabed by strong currents. Orange-yellow branches bore pink polyps. A piece of shell brought by the current stayed between them. With the next strong surge, it tipped over, slid through the fork and landed below. A crab examined it at once. Above it, the tentacles were free again, and everyday life in the little colony went on.

People kept heavy nets away from the red coral. This preserved its fixed home. High above it, food formed in the upper sea; some later came through the dark water to its green polyps. Turquoise-green polyps sat on a red relative. A little animal brushed one of the feeding arms and became caught. Straight afterwards, another polyp opened. In this way, the many little residents caught food for their colony. Outside, the sea kept changing. Here, what mattered for now was the next meal and a firm place on the seabed.

People could protect individual rocks from fishing gear, but could not redirect every flow of water. Even protected places received substances from far away. Food, small neighbours and unwanted particles therefore had to share a path between the pink branches. A pink relative stood where a small gap remained between rocks. Its colourful crowns moved in the water, some blue, others yellow or violet. A fish paused before it and only just fitted through. Behind it, the current gathered speed again. The family caught food while its visitor was already seeking another shelter on the far side.

Ships travelled above the reef, but its branches stood far below their sight. Only research devices had made them known. People now planned new work at a distance so that food could keep flowing freely through the colonies. A yellow trunk split into one pink and several pale branches. Blue polyps sat between them. A prawn climbed until it felt the current more strongly. Then it turned back. The coral stayed where it had grown. Its fine catching arms reached food without it having to swim after a prey animal.

Food did not always sink evenly from the warming sea surface. People studied how much of it reached the seabed. Down below, the animals had no garden to tend; they had to catch what the current carried past. Green and yellow branches stood close together. When the water cleared, a little fish could see the whole coral again. It swam all the way around it, then disappeared behind the base. The polyps were still busy feeding. Even a clear day could be a busy day on the reef.

A research device stopped at a distance beside the rocks. The people controlling it from the ship wanted to see the water's paths without touching branches. Meanwhile, little guests searched for calmer places among the colonies themselves. Green and orange-yellow branches reached up from a blue base. A prawn searched for a path between them. On one side, the current pulled harder. It climbed to the other and rested beneath a fork. The pink polyps above it caught small prey animals. So the same branch could be a workplace for its residents and a hiding place for a guest.

People had closed part of the deep seabed to heavy fishing gear. The old stones stayed in place there. Among them, coral larvae found somewhere to hold on, while the current brought small prey animals from the open water. Some descendants of the family had blue branches and green and purple polyps. One such colony grew between two stones. At first, a small fish could fit beneath its lowest branch. Later, it had to swim around the outside. The reef grew slowly, but a great deal changed for its inhabitants along the way.

Up on the ships, people saw only glimpses of the deep world. Their research devices searched for surviving colonies among damaged slopes. A bright dot on the screen showed them where life remained. Many hundreds of metres above the reef, the sun stood over the sea. Not a single ray reached the pink coral below. Only the lamp of a research device made its branches visible. Sunken plant remains lay beside its base. A crab pushed beneath them. As the circle of lamplight moved on, the polyps kept catching food from the current in the dark water.

People sought protection from particles their cities and ships had brought into the sea. A fine covering surrounded a yellow relative. Sunlight was no concern down here; the covering had to keep dirt out and let water through. In a lamp's glow, the new family branch was entirely yellow. A thin, clear covering lay around its branches. Some particles slid past outside; others reached the colourful crowns with the water. The helpers checked the edge so it stayed open enough. Inside, polyps waited for food while the great dark current passed outside.

Violet corals in the deep sea needed no daylight to eat either. People found them in the light of their diving robots. Nearby lay broken branches that heavy fishing equipment had dragged over the seabed. A violet colony stood beside smaller fish. Its polyps were almost the same shade as its branches. One fish disappeared behind the trunk; two others moved on. The coral stayed behind. When the current brought fresh seawater, its feeding arms stretched out. Small food animals arrived, and the wait had been worthwhile.

A research device pointed its circle of lamplight at the purple branches. A larger fish swam through the beam. For a moment, its shadow fell on the reef before the device moved on across the dark seabed. Purple and blue covered the branches of a coral. A large fish swam past in a research device's circle of light. Its shadow slid across the trunk. A smaller fish darted into a gap. When the visitor had moved on, it came out again. Then the lamp moved on too. The polyps caught their tiny prey animals in the dark water.

A research ship stopped high above the three-coloured coral. People lowered measuring instruments because their emissions had changed the sea. Below, the polyps carried on with their daily search for food. A fish swam alongside an unusually colourful relative. It was orange below, green in the middle and pink above. Its polyps were blue. The fish circled the base first, then the upper branch. By the time it moved on, some polyps had caught food. Their many colours did not change the fact that they all had to eat.

People discovered the blue-green and pink relative in the light of their robot's lamps. They mapped the reef so that planned cables would pass around it. Slowly, a map took shape above that could prevent many broken branches below. One relative had a blue trunk. Pink lay on its branches to the left, green to the right, with yellow and red polyps between them. A small crustacean crawled beneath the lower twig. Above, the current flowed past. The coral caught food. The crustacean kept searching along the seabed until it too found something suitable.

In the light of a diving robot's lamps, the colony looked especially colourful. People recorded it on a map and kept bottom nets away. This allowed the slow years of its growth to create a large habitat once more. Yellow, blue, green and red lay on a single trunk. The colourful colony belonged to the same big family as its pale neighbours. A polyp caught food on a violet twig. Another was still waiting on a yellow one. Then the water turned. Now something arrived there too, and the feeding arms closed.

People did not observe the same warming everywhere. Especially cool currents could also arrive in the depths and change course. Such changes remained difficult for the family if a new flow brought hardly any food to its branches. The next branches stood powder blue in the dark water. Pink and lavender crowns sat upon them. A cool current passed the rock, bringing food. The polyps opened one by one until small tentacles swayed over the whole body. A passing fish paused briefly, then vanished behind the family's pale blue branches.

As people mapped the seabed, they now steered their devices more carefully around living branches. One touch could break branches that had taken a long time to grow. The little animals between the forks, meanwhile, had to pass them without bumping into them. Blue, yellow and purple bands lay around the branches of a colourful coral. A prawn climbed up them. It stopped before an outstretched crown of tentacles and turned back. It found another way between two forks. The reef had plenty of room for small visitors, but everyone had to consider its residents.

On land, people searched for the connection between their lives and the distant seabed. Research devices collected water samples. Meanwhile, down below, everything centred on the next small meal that a connected coral body could share among its polyps. Polyps of many colours sat on a turquoise colony. Small animals were joined into one shared body. What one caught could feed its neighbours too. As the current passed an upper branch, fine tentacles caught food there. Further down, a polyp moved that had just failed to reach anything.

People's emissions had warmed the sea over a long time. This change did not stay only at the surface. Research devices checked the water from which the colonies received their food in the depths too. An especially colourful coral had grown over many years. Many little animals had already found shelter among its red, blue and yellow branches. Now a new fish arrived. It did not yet know the reef and hesitated before the fork. Then it slipped inside. Behind the wide trunk, the water was calmer than it had expected.

At the edge of a protected area, people left the seabed untouched. Food still came with the open water. Beneath the surviving branches, prawns briefly found a hold when a stronger current carried them sideways. An orange coral bore green polyps. The current pushed a small prawn sideways against the trunk. It held on briefly and found a calmer foothold between two branches. Then it swam on. Tiny prey animals remained in the water behind it. The polyps opened their fine tentacles and caught what they could reach.

People brought lamps and instruments to the deep rocks. They checked how far changed water had spread. The pale tips remained visible in the light while more particles drifted from the darkness between the polyps. A delicate peach shade covered a pale relative's upper branches. Lower down, its body stayed almost white. The current brushed the tips first, then passed through the lower forks. More polyps waited there for food. A tiny creature became caught. This small catch mattered more to the family than the difference between its pale colours.

The dark polyps lived in the same deep sea as their colourful neighbours. People studied the reef with lamps. They kept fishing gear away and searched for lost lines before even more animals became tangled in them. Colourful and dark polyps sat side by side on an orange relative. A little fish passed the upper branch, then the lower one. The colony stayed firmly anchored to the seabed. When the water brought fresh prey, feeding arms closed here and there. Soon the little animals were waiting again for the next movement among the branches.

Only a few larger colonies remained beside an old trawl track. People wanted to protect these remnants in future. For a little fish, the distance to the next hiding place was still large when it had to cross the open seabed. A red coral bore yellow polyps and blue tips. A little fish swam so quickly between its branches that it stirred up the sand at the base. Behind them, it stopped. No one followed. It had found a hiding place. After a while, the water cleared and it dared to go out again.

People found the colourful colony among many other deep corals. They recorded the habitat with cameras. Then they set a boundary for heavy bottom nets so that the slowly grown place would not be damaged again. One relative was colourful from its base to its highest branches. Yellow, green, blue and pink lay close together. A fish disappeared behind the trunk and came out again on the other side. The polyps waited in the water. Then food was caught on several branches at once, and for a while the whole colony was busy.

Emissions from cities and factories warmed the sea, and rubbish sank all the way down. The colourful coral family lived in the midst of these changes. People collected things that had sunk and also had to cause less new harm. Red, pink, yellow and blue stood side by side in the family reef. One coral brought together an especially large number of colours. A fish swam around it, dived between two branches and returned. Life was still moving here. The little residents carried on doing what they needed each day: eating, growing and making way for one another.

Fishing boats now kept their distance from a surviving piece of coral. The deep branches were still exposed to moving water. Small inhabitants sought calm between the forks when the current grew stronger outside. On an orange coral, a prawn found a free place between the branches. It stayed there while colourful polyps all around caught food. When the current turned, its long feelers danced in the water. The prawn moved deeper into the fork. There it could wait until things grew calmer outside again.

People now measured substances left in the sea by their wastewater and equipment too. The family could not follow the instruments. It stayed on its rock and had to manage with the water flowing past its orange and pale branches. At the very top right, a relative wore an orange stripe. Beside it sat an equally warm-coloured crown. A shrimp came along the branch, paused before the polyp and climbed on along the other side. The current brought fine particles. Some caught on tentacles; others flew past, only to reach the pale family's next crowns.

People shone their lamps on the reef only to observe it. They could not feed the coral that way. If changed currents brought less food, extra light did not help its hungry polyps. A red polyp sat among many yellow ones on a deep blue colony. Further down, some were turquoise. When tiny animals swam past, the feeding arms stretched out. Nobody needed sunlight for that. Down here, food came with the water. The colony caught what it could reach and let the rest travel on with the current.

A measuring instrument on the rock stayed longer than a single research visit. People wanted to understand the quiet days too. Below, food sometimes came late, sometimes all at once, while the coral kept its fixed place. A red polyp sat at the top of a pale coral. A little fish swam close past it. The polyp drew in its tentacles and waited. Further down, its neighbours reached for food. Soon afterwards, it opened again. The water had no fixed timetable. The little animals had to be ready when something edible arrived.

Machines had cut a track in the seabed for a new undersea cable. Fine sand had been left beside it. The current slowly shifted it between the stones, where little animals searched for paths. An orange stripe lay in the middle of a very pale coral. A young crab crawled past the base and got caught at a fork. Carefully, it looked for another way. Above it, the polyps opened. It slipped between two stones while the current laid sand over its tracks.

A new pipeline had stirred up a cloud of mud far beside the reef. People changed their plans, but the particles were already on their way. They sank among rocks, where every stronger movement of water could later move sand again. Narrow red lines ran over a pale coral. Fine sand caught in the fork beside them. A prawn brushed past it with its feelers and withdrew. Soon the current grew stronger. It took the grains away. The polyps could open freely again, and the prawn cautiously ventured between the branches.

People collected loose plastic remains beside the reef. Even so, no safe route through the sea could be built for tiny larvae. The current carried them between old traces and protected rocks to new places. Tiny larvae drifted in the water beside a delicate pink and green coral. Some were carried far away. One stayed briefly in a little swirl by the trunk, then drifted out too. The family could not know where its descendants would find a hold. But on bare stones, room waited for new little colonies.

For a long time, large amounts of exhaust gases had been produced on land. Some entered the sea as carbon dioxide and changed the water. So researchers checked not only the temperature, but also how the coral skeletons were doing. A pink-orange section lay in the middle fork of a pale coral. A small seashell caught in that very spot. The current pushed it back and forth until it turned and fell to the seabed. A crab came out of its hiding place. For it, the shell was a find. For the polyps, the way to the water was clear again.

Researchers found only a few undamaged colonies at an old fishing site. They marked the area on their maps. For the small fish on the seabed, these remaining forks already made up all the available hiding space. An orange branch reached out of a pale colony. Blue tips lay opposite. A little fish pushed between them and stopped in the fork. The current tugged at its fins. It moved back a little until the trunk gave it cover. The reef was full of narrow places like this, which only suited the smallest inhabitants.

A lost piece of fishing gear had been removed from near the reef. People took away the foreign plastic, but left stones and seashells in place. Small inhabitants could keep using these natural hiding places. One side branch on a pale colony was vivid red. An empty snail shell lay directly beneath it. A crab crawled over, examined the entrance and briefly disappeared inside. Then it came out again. It was too small. Above, the polyps kept catching food while it searched the reef for a house that fitted better.

A research ship had discovered old fishing tracks around the rock, and people had protected the area. Small animals searched for food among the remaining forks. The open ground beside them offered little cover. Fine blue stripes ran across a pale body. Pink polyps opened on the branches. A little crab crawled along the base and stopped behind the fork. From there, it watched a fish passing through the open water. Only when the large visitor was gone did it keep searching for food among the stones.

A few corals still stood at the edge of an old fishing track. People lowered their equipment into the water further away. Little visitors could stay among the surviving branches, while larvae searched for new ground with the current. Pink polyps sat among yellow and orange branches. A crab wandered past the base below and disappeared behind a stone. In the open water, a larva slowly turned around. The current carried it along. Many animals came and went in the reef. The coral family stayed at home here through its firmly settled colonies.

A new work site on the seabed would have put the colourful reef in danger. People changed the plan after seeing pictures from their diving robot. This left the rooted colonies standing instead of disappearing beneath cables and stirred-up mud. Many bright colours came together in the upper half of one relative. Below, it stayed pale. A little fish first swam around the colourful part, then dived beneath a white branch. It stopped there. The coral stretched out its polyps. Food passed both parts whenever the current took the right route.

The machines at an old building site had long been shut down. Yet the current still shifted loose sand there. When new heaps reached the corals, little fish had to find other gaps until the water wore them away again. An orange colony grew beside a stone. When sand moved through the reef, a small heap stayed behind the stone. A fish tried to settle there and bumped its belly. It swam higher and found space among the branches. The sea changed even familiar hiding places without moving the coral from its spot.

Researchers had marked the last large colony on this rock on their maps. Heavy equipment was to take another route. Small animals still found space beneath the branches, while more open ground lay outside. A pale yellow coral bore pink polyps and a few blue tips. At its base, a little crab searched for a hiding place. Between two stones, it found a gap that was just wide enough. As it disappeared inside, food drifted past the branches. The coral and its guest could use the same place in different ways.

Researchers brought measuring instruments to a deep rocky ridge. There they wanted to track how earlier emissions had changed the water. The corals could neither explain their colours nor leave their place. A coral was pink below, blue in the middle and almost white higher up. A little fish swam alongside it. At the blue fork, it disappeared behind a branch. A moment later, it emerged on the other side. It had found a short way through. The passage would have been too narrow for a bigger fish.

After an old fishing area was closed, fine mud remained on the seabed for a long time. Even small inhabitants stirred it up again as they searched for food. People had to keep new work at a distance so that no more kept being added. A brown section ran through the middle of a pale coral. Beside it, a fish swam and searched the seabed for food. It pushed sand aside and stirred up a small cloud. Some polyps withdrew. Only when the water cleared again did they open and catch their own much smaller prey.

Above, large ships caught fish; below, small inhabitants searched for food among the remaining rocks. People were now protecting some reef remains. There, colonies and their guests could use the same space of water in different ways. Blue spots ran across a pale trunk. A tiny fish swam alongside it and stopped before a red polyp. The tentacles moved. The fish backed away and looked for food behind a stone. Both lived on what the sea brought, but they found it in different ways.

In the lamplight, people saw green, pink and blue branches among the deep rocks. They changed the planned route of a cable. This preserved the firm place where the colony could slowly keep growing. Green, pink and blue shared the trunk of one relative. Some polyps were very dark; others were pale. A fish swam around the colony once, then stopped under a side branch. When food arrived, it had to come out again. The polyps had it easier: they were already waiting where the water flowed between their feeding arms.

The heat absorbed by the sea above did not stay at the surface. Currents carried changed water into the depths too. Human carbon dioxide also changed the water's chemistry. Different challenges awaited at a dark rock face and on a deep-sea slope swept by currents. What helped here might do little there. Over time, the family's larvae found different places on the dark deep slopes. Some settled on steep rocks; others grew in sheltered cracks. Food passed often here, rarely there. Over many generations, the branches looked different. Some had short, firm branches, others longer ones. None of this happened through wishing, and not every new place remained habitable.

People measured water conditions beside the pale coral. Carbon dioxide from their emissions entered the sea and changed it. The colony stayed in its fixed place while the people above searched for ways to reduce emissions. A blue patch lay higher up, and a pink patch in the middle of a pale relative. Between them, the body stayed white. A little visitor squeezed through a gap in the trunk. Above, the current flowed past. By the time it came out on the other side, some polyps had already caught food. Others still waited with their feeding arms spread.

Working on the seabed, people stirred up fine mud. The cloud travelled with the water until it reached open polyps. Colonies had to shed the particles, missing some meals from the current as they did. A fine film of mucus covered the next branches. When mud arrived, some stuck to it and was carried away again. This took energy. The colony waited until the cloud passed and cautiously opened its polyps. Older, thick branches lay beside it. They offered support, but they too needed water in which their skeletons could remain intact.

The fishing boats had disappeared from this part of the sea, but their traces were far from gone. Loose sand lay in old grooves. The moving water kept carrying it between the remaining branches. An orange-yellow side branch stood out on a pale body. Fine grains of sand gathered behind it. A crab tried to climb over the little heap, slid back and looked for a flatter path. Meanwhile, the current turned. It took some grains away and made a new narrow passage in front of the coral.

A measuring station monitored the water among the deep rocks. People wanted to understand the effects of their emissions better. While they compared numbers above, the blue polyps on the orange branches waited for food. Blue polyps sat on soft orange branches. When a larger fish passed over the colony, things became unsettled for a moment. A little food animal swirled past to one side. The first polyp missed it; the next caught it. Then the fish was gone. The coral stood still in the water again and waited for the next little animal.

People had changed the community of sea animals through fishing. Some neighbours grew rarer; others visited more often. Not every visitor between the dark rocks was harmless; the thorny relative shared its home with hungry animals. Little thorns stood along a pink colony's edge. A hungry visitor approached, stopped before the points and moved on. Between them, the polyps kept catching tiny food. The family reef had many ways to protect a branch. This branch wore its answer along its edge, but even the sharpest thorn could not help against warm water.

On land, people continued burning large amounts of oil and gas. In time, some of the extra heat reached deep water too. People sent measuring instruments down and searched for reef sites that were still suitable. Light blue and yellow met on one trunk. Pink polyps were scattered over it. A little resident crawled among the lower branches and stopped under a ledge. Above, the current flowed past. Here, shelter and open water lay close together, and the different animals used the space in their own ways.

People changed fishing grounds and left waste in a sea whose currents were changing too. Different bodies of water met at the deep rock. Between differently coloured branches, small neighbours had to find shelter and polyps had to find food. A spiny relative stood on the rock, pale green above and sea green below. Brown points outlined its edge. A small visitor touched them with its snout and drew back. Meanwhile, polyps on both halves caught food from the same current. Their colours differed, but no crown could simply do another's work. Each needed its own share.

Human work on the seabed put sand into the water again. The current carried it among the lower branches. People had to keep far enough from the reef so that the polyps would not constantly have to cope with such clouds. Blue lines ran over a pale trunk. Some polyps lower down were yellowish. A little grain was pushed past a twig, curved round and sank to the seabed. It stayed there. The current now slipped higher through the branches. With every change of water, new little food animals arrived for the coral.

While dragging heavy nets, people had churned up the seabed beside the reef. The current carried water and dust sideways through the branches. Not every strong movement of water was new, but the equipment had brought extra dirt. A surge of water swept sideways past a pale coral. A little fish had to swim hard to hold its place. At last, it gave in and let itself drift a little way. The coral stayed firmly on the seabed. When the water grew calmer, the fish searched behind its lower branches for a better place to wait.

People left dissolved substances and small particles in the sea, while the current brought different amounts of food to different places. A colony's polyps remained connected. Even so, the arriving stream of food had to reach its furthest branch regularly. Red lines followed a relative's turquoise-green branches. Beneath them lay the little pathways by which polyps shared food. When something was caught at the front, not all of it reached the last tip at once. The family needed time. As the current moved on, the crowns on the other side gradually opened too.

Mining and building in the sea, people had loosened much seabed material. The particles settled elsewhere. Firm rock supported the family, but with each new cloud, the polyps had to stop catching food and begin again later. A pale relative stood on a dark rock. Fine blue, red and green lines ran through its branches. Below, a small neighbour squeezed past the base and stirred up sand. The ochre polyps briefly withdrew. Once the water cleared, they reached for food again, while the rock held the whole colony quietly in place.

Ships and factories had contributed to warming through their emissions. The warmth was not spread evenly everywhere. So people lowered measuring instruments at the edge of the deep reef and watched the water over many years. A soft orange relative with many colourful polyps also grew in the reef. It stood firm while a little piece of leaf drifted past. The piece was too big to eat. It caught briefly on a twig, then came free again. The polyps caught the much smaller animals that arrived in the same current.

People measured temperature and water movement at the edge of the deep reef. Their emissions had changed conditions in the sea. From the ship, they followed when food was carried among the yellow branches. A yellow relative had blue and pink polyps. When the water flowed more strongly, little food animals brushed past the outer twigs. Less reached further inside. A fish swam through and disappeared again. The polyps kept waiting. After a while, the current turned, and now it reached the other side too.

Over many years, human emissions changed the heat in the sea. So a ship studied the water around this pink colony. People watched when the current brought fresh seawater and food among its branches. A pink relative carried blue polyps on every side. The water flowed past them sometimes faster, sometimes slower. A little fish waited behind the trunk. When food came, it darted out. The coral stayed quietly in its place. Its feeding arms could reach only what passed close enough to the blue polyps.

People changed the sea's heat and substances. Longer pauses fell between deep currents, leaving food scarce. The branching family still depended on its inner connections and the next surge from outside. Golden-orange branches stood on the next rock. Fine red and blue lines ran along them. In this family, inner pathways had branched out, carrying food from one polyp to another. Yet none could share across unlimited distances. When a rear branch caught little, the colony waited for the next surge to reach those crowns too.

Warming caused by human emissions had changed the sea in many places. People used measuring instruments to follow the water's paths. The differently coloured branches all stood in darkness and received their food from the current. Corals with pink, blue and orange areas stood in the family reef. On one, these colours came together on the same trunk. The water pushed a small food animal past one branch. Another polyp caught it. Although the twigs looked different, their many little residents were connected and fed the same colony.

Only the lamps of a diving robot revealed the red coral's colours. Sunbeams did not reach this place. The people had come down to see which parts of the reef their fishing had damaged. A red relative carried pale polyps. In the dark water, its colours could only be seen when a beam of light fell on them. It did not need that light to eat. Its feeding arms waited for little animals. A little further out, the current flowed more strongly. Descendants of the family lived there too, each in its own fixed place.

Fine threads from human waste drifted between the rocks. Some colonies also bore imagined protective threads of their own. Helpers had to look closely to see what belonged to the family and what merely blocked its path to food and water. Rainbow threads played around the next relative. They stretched over golden and pale branches, moving with each new surge. A polyp briefly hid behind them. Then a thread bent aside, revealing its crown again. The current took some loose particles away. Small helpers had to carefully free the rest from the tangle.

Over time, a lost net broke down into finer and finer threads. People could no longer find every one of them. Some drifted through the depths, where corals reached into the water for something to eat. A few blue polyps sat among the pale ones on an orange coral. A fine thread drifted through the fork. It touched a branch, slid along it and came free again. Soon afterwards, a small prey animal arrived. This time, the tentacles caught it. Not everything the water brought past could be eaten.

People did not control the currents' routes, although they changed the world above. Some deep rocks received food irregularly. Between the branches, the pictured threads moved with the water; they could not replace a reliable supply. Fine ribbons moved beside a mint-green relative. When water came, they swayed, brushing past the colourful crowns. Below, small reef shapes lay in the sand. A fish swam around them before slipping between the branches. The current divided at the base, circled briefly, then resumed its journey through the family reef.

People measured the current at the dark reef for a long time. Their emissions were changing the climate and, with it, conditions in the sea. The pink coral still needed water to carry food among its branches. The water around a pink colony looked blue. A little fish glided close past the trunk and disappeared upwards. Below, the polyps kept at their work. From time to time, food reached them. Between meals, hardly any movement could be seen. Quiet hours like these were part of the family reef's long life too.

Above the reef, people studied which food sank all the way down. Their emissions had changed the upper sea too. Among the yellow branches, the polyps kept waiting for small animals and edible particles. A yellow relative carried blue polyps. Fine grooves lay in the seabed below. A little animal crawled along them until it disappeared behind the trunk. Further up, food was being caught. The reef had many levels: seabed, base, branches and open water. Different residents found a place everywhere, as long as enough food and space remained for them.

People had put fine waste and clouds of sediment into the water. Imagined root filters formed around some colonies, catching particles. Filtering alone did not make the water rich in oxygen; fresh current still had to reach the family in the depths. Root-like filters spread beneath a pale relative. They were part of a new protective system at the base. Orange bubbles rose beside them as water passed through fine openings. The polyps above still had to reach for food. A small neighbour crawled over the edge, and the current divided around both before meeting again between the branches.

People wanted to understand how water and food travelled through the reef. They set measuring instruments down near the red polyps. Because their actions could change the seabed, even their observations had to avoid damaging branches. The water turned in little circles beside a pale colony. Its red polyps stood right in the middle. A food animal curved round, brushed a feeding arm and was held fast. Others drifted on until the movement changed again. The coral could not decide the current's route. It had to make use of whatever passed close enough.

Human emissions had warmed the sea, and some deep reef sites had become unsuitable. A cooling coral was part of the imaginary rescue. People measured the small area it affected and still had to reduce the causes of warming. Where other corals could no longer live, descendants with a special ability grew. They cooled the water around their branches. Soon a little fish arrived. Later, more animals found room there. A yellow and pink colony stood in the middle of this new neighbourhood. Its cooling helped others too, but it could reach only a small part of the sea.

Up by a distant coast, people had damaged kelp forests. Torn pieces sank through many layers of water. One reached the cold reef and caught between its branches. A colony wore orange and yellow in the middle, blue and purple on its outer branches. One day, the current pushed a piece of kelp between its twigs. A fish tugged at it until it came loose. The leaf drifted on. Behind it, the little polyps could reach the water freely again.

Warming and changed currents made fresh seawater harder to supply. People measured oxygen down below too. The green fantasy glow made the difficulty visible but did not solve it; the family still needed water with oxygen to breathe. Small green bubbles shimmered around a pale relative. Yellow rays traced a glow between its branches. In this corner of the future, tiny fellow residents glowed too. Yet light alone could not help the family breathe. Fresh seawater had to arrive. When the current finally returned, the fine tentacles moved again, and the glow danced around their open crowns.

A device on the seabed measured the water's movement beside the reef. People wanted to plan pipelines and fishing sites further away. Below, every rolling snail shell revealed how strongly the current was flowing through the rocks. Water passed a pale coral from both sides. It brought food and shook everything that was not firmly attached. An empty snail shell rolled over the seabed. It stopped behind the trunk. A little crab examined the find while above it, the polyps stretched their tentacles into the calmer current.

Researchers used instruments to track where water flowed over the rocky ridge. People had kept fishing gear away from it. Now tall branches remained standing, with spaces where a little fish could shelter from particularly strong surges of water. A little fish sat beneath a blue fork and waited. Above it, pink polyps stretched out their tentacles. First the water flowed from the left, then from the right. Each time, the fish moved to the calmer side. The coral could not change its place. Its branches reached water from several directions.

People found the blue and pink coral deep beneath the surface. They measured the water there, which their emissions had changed. At the same time, they kept heavy fishing gear away so that its fixed home would remain undamaged. One relative was blue above and pink below. A fish swam from its base to its highest branch, then disappeared into the open water. The colony stayed behind. Its polyps waited on both parts of the body. When food arrived, it was caught above and below. The many little animals belonged together, even if their branches looked different.

People kept trying new protective coverings and stores because temperature and water quality remained hard to rely on. Small bubbles were among their unusual ideas. Yet fresh seawater still had to arrive below before the protected spaces were eaten bare. Red bubbles floated above a pale relative, blue ones beside its base. A small fish nudged one and followed it upwards. The colony stayed on the seabed, catching food from the current. Many strange things filled the family's protected spaces. But the polyps only became full when their tentacles caught a tiny meal from the water.

A measuring instrument on the seabed recorded how the water's movement changed. People could read the numbers later. The little animals felt the same change at once: behind a trunk, it stayed calmer than beside it. The current brushed over a silvery-blue coral and its orange polyps. A small calm patch formed behind the trunk. A prawn stopped there. It moved its feelers as though testing the water. Then it swam carefully around the fork. Just beyond it, the current was already pulling harder again.

A research ship left plates and measuring instruments beside a protected piece of reef. People wanted to learn where new larvae settled. For the young, what mattered was firm stones and water that brought food. A coral was red at its base, then orange and yellow further up. A larva caught on a stone beside it. The current tugged at it, but the stone gave it a hold. The little animal became a polyp. Long before it could grow branches of its own, the family already had a new member in this place.

Human emissions and wastewater changed water that flowed through the deep slopes much later. Here too, the family had to manage with what came from outside. The current shared its cargo among all open polyps. One relative wore mint above and pink below. The current came from the left, brushing the higher branches first, then gliding to the base. More polyps waited there. One little particle caught; another flew on. So the sea never shared its meals quite equally. The family caught what it could reach and waited for the next current.

People had burdened the sea with ever more substances. The current carried them through branches and cracks. A protective flow could remove loose particles, but dissolved substances did not disappear that way; their causes had to change further above. Orange lines wound along a pale relative's branches. A fine stream of water carried loose particles away. Some collected at the mint-coloured base until little helpers removed them. The polyps did not all wait equally long. Some received clear water sooner, others later. By the time the last branch was clear, several crowns at the front had already caught their meal.

Researchers laid maps of old fishing tracks beside new images. Tall branches were still missing from some areas. Among surviving corals, the current remained full of little paths along which food and loose pieces of shell arrived. Red and blue lay close together on this coral. The water brushed around its branches and lifted a small shell fragment at its base. It rattled against the stone and came to rest. A crab emerged, felt it and moved on. Above it, the colony caught food without leaving its fixed spot.

People now laid new pipelines around the known reef. This left its firm ground untouched. The current still flowed between the branches and brought food, while small fish found calm behind the trunks. The base of a pale blue coral held firmly to the seabed. When the current grew stronger, a little fish darted behind the trunk. Above, the orange polyps reached freely into the water. Some drew in their tentacles, others caught food. The fish waited. Then it carefully let itself be pushed across to the next stone.

People used lamps to examine a pale colony with blue marks. Fibres and particles from human waste drifted nearby. With the next surge, a clean branch could again receive something lost far above. Dark blue marks lay along a pale relative's lower branches. Beside them, the current carried loose threads past. A small neighbour paused between two crowns, then sought another route. The family held its place on the rock. When water flowed more freely again, several polyps opened, even where the blue marks crossed the body.

A heavy net had left a wide track near the reef. The tall branches were missing there. So small animals sought shelter beside the colonies that had remained standing among untouched rocks. A red coral with yellow polyps stood above the brown seabed. A crab pushed a grain of sand aside and disappeared beneath its base. When a stronger current came, it stayed there. Above, the water reached the branches. The polyps caught food while below, behind the trunk, everything stayed much calmer.

Researchers placed small instruments in the current without touching the corals. This showed them that not every rock received the same amount of food. A larva also had to find a place where water passed by. Blue at the base, red in the middle, green and yellow above: that was how another branch of the family looked. A larva drifted close past its branches. It was so small that no fish noticed it. The current carried it to an empty stone. There it held on and began a new life.

A research ship had placed devices around the rocky ridge. They showed how unevenly the current reached the reef. People wanted to plan future work on the seabed so that the water's routes stayed open. Water flowed in long paths around a red coral. A little fish tried to swim against it. It barely made progress and turned behind the trunk. There it could rest. Above it, the colourful polyps reached into the current. They caught food in a place where the fish found it hard to stay.

People had found no shared solution for every deep reef site. Coverings and water movers helped in some places; elsewhere, fresh waste immediately caused trouble again. It remained important that the current still reached the delicate polyps between colourful branches. The next relative was a colourful patchwork. Pink, red, green and yellow met at its forks. A little stream ran along one side, carrying loose particles away. A polyp briefly vanished behind the blue veil, then reappeared. The family needed no single colour as long as enough water and food reached between its many branches.

Where people kept bottom nets away, the green branches could stay standing. Measuring instruments also tracked food and water conditions. Among the deep rocks, a home was to survive where descendants could grow for a long time to come. A turquoise-green relative carried blue polyps right out to its outer twigs. When the water flowed more strongly, food reached the exposed tips first. Further inside, the little animals had to wait. Then the movement turned. Now something was caught behind the trunk too. The rooted coral made use of the place where it had grown.

Above the reef, heavy fishing gear had stirred up sand. The cloud only reached the depths later. Between two such surges, clearer water carrying small prey animals flowed through the branches again. Further out grew a vivid blue coral. Its colourful polyps reached out in all directions. A swirl carried sand past and made the little animals draw in their tentacles. Once it had settled, they stretched them out again. Soon afterwards, food arrived. The family lived with the changing rhythm of waiting and catching.

People laid small pipes and water movers at individual deep reef sites. The systems could only help locally. While they ran, substances kept arriving from the inhabited sea; helpers had to check that the current really reached the polyps. A thin stream flowed around a pale green relative. A small device above helped keep it moving. The pink crowns sheltered behind it without being entirely cut off from the sea. A helper checked the pipe and pushed away a trapped particle. Water reached the whole edge again, until the lower polyps opened their tentacles too.

People had changed the climate, and the water no longer spread warmth and food exactly as before. Measuring instruments now stood among the deep rocks. Researchers on a ship watched the changes over many years. Violet and blue relatives also belonged to the family. One colony had especially bright colours above and below. When the current turned, food came from the other side. Now the little animals reached different polyps first. The trunk stayed firmly on the seabed. Only the water had changed its route through the branches.

New disturbances appeared on the seabed. Where people extracted material or dragged heavy equipment across the bottom, clouds of mud rose. The family had to protect its delicate polyps and still reach food. No sun shone over its branches. Its unusual roofs and coverings were ideas for life in dark water. A soft veil moved beside a pale relative. Its fine threads held back some stirred-up particles. People had fixed the protection to the deep rock and checked it regularly. A small fish sheltered between veil and branches. The polyps waited for food to pass through the slowed current again. When the mesh was full, it had to be emptied.

A line had become caught around the coral's dark base. People had to free it carefully with a gripping arm. Simply pulling could have broken the trunk, even though they meant to help. One relative had a dark base and a dark branch tip. The rest of its body was pale. Little food animals passed its polyps. Below, the current pushed sand over the seabed. A grain rested briefly against the trunk, then was carried onwards. The coral held fast and waited for the next meal.

Mud from human seabed work travelled on as a cloud. A fine green mesh was meant to protect individual colonies. In the darkness, it was an imagined filter, not a seagrass plant; collected particles had to be removed from the shelter again. A green fan-shaped veil surrounded a pale relative. Fine threads bent with the water and straightened again. Some particles caught on them. Little helpers had to carry them away so the veil did not become too heavy. Behind it, the current reached the polyps in smaller surges. The family waited patiently between one sweep and the next.

During work on the seabed, people had stirred up dirt. The sinking particles threatened the open polyps. Now helpers tried to catch some of them without also blocking the current that carried food. A diving robot stretched a large sheet above a pale relative. It was meant to catch sinking dirt. People had even thought about sun protection, although no sunbeam reached here. A special layer lay on the body, and long clinging extensions held fast below. The robot left the sides open. Water carrying food still had to be able to flow between the branches.

Seabed work had left loose particles travelling with the water. The green fan offered imagined protection from such clouds. It was not light-needing seagrass expected to grow in the family's dark home. To the right of a colourful relative stood a large green fan of fine strands. When water came more strongly, it bent and slowly straightened again. A small fish hid behind it. Between fan and branches, the movement was calmer. The polyps caught food there while particles shot past outside and the strands bent aside once more.

Plastic ropes and other human waste shed fine fibres into the water. Some caught on the reef. The imagined protective mesh therefore needed care; a full filter could block the family's access to food as much as the rubbish itself. Blue and green threads surrounded a relative with violet crowns. They caught much that would otherwise have entered the branches. But the net had to stay clean. Little helpers pulled particles out and carried them away. Only then could enough water pass through again. The family waited behind the threads and slowly opened its polyps.

Fishing had stirred up mud from the seabed again. So people left more distance between their fishing routes and the deep reef. Dark stripes on the branches offered no reliable protection from heavy equipment. Dark stripes circled some branches of a pale relative. A little fish paused in front, then swam around it above. The polyps kept stretching into the water. Below, a larva landed on a stone. It stayed there. As the fish moved on, a new piece of family history began beside the dark stripes.

Fine plastic fibres from ropes and waste drifted far below the ships. People built and invented filters for threatened colonies. These needed care; if too many particles gathered, protection itself became an obstacle to food. A loose weave of blue and green threads surrounded a pale relative. It moved with the water and caught loose particles. Little helpers cleared gaps again. Behind it, room remained for polyps reaching for their meal. The current took a detour through the weave, but it could not stop entirely if the family was to keep living here.

A new cable was to be laid across the seabed. People first sent a diving robot and discovered the coral with the dark band. The cable route had to keep its distance so that the coral's fixed home would not be damaged. A dark band ran around the lower trunk of a pale relative. Below it, the base was pink; above it sat pale polyps. A little fish swam past and disappeared behind a stone. The coral stayed behind. With the next flow of water, its feeding arms opened wider. Here too, daily food came from the current.

Ships and wastewater had spread small plastic particles into deep water. People sought filters and new protective ideas. Some looked like sun protection, although the corals below needed shelter from dirt and lived in darkness. Deep below, a yellow relative stood on firm grey ground. Little helpers collected particles from its surface. Beneath a thin covering, the polyps stayed open. A lamp showed people where rubbish was still caught. They took the collected pieces away. Only then was there room for the next cargo the current brought uninvited to the branches.

Over a long time, plastic in the sea had broken into smaller and smaller pieces. People could collect large pieces; tiny ones were harder to find. Currents carried them to hungry polyps in the dark reef. Tiny plastic particles drifted between the branches. Small capsules sat on parts of the colony, able to break down rubbish in this future story. Yet the polyps still had to eat; their helpers' work took energy. Where too many particles arrived, tentacles closed. Then the family waited for a clearer current before continuing its difficult daily life.

Through their emissions, people had added ever more carbon dioxide to the water. This became a problem for calcium carbonate skeletons. In the future story, helpers sought protective layers; a colourful glow alone could not reverse the changed water chemistry. A shimmering veil surrounded a pale relative. The family called it Corallus colorius because its colourful crowns hardly seemed to keep still in the glow. Thick goo on the trunk protected delicate places. Yet good water still had to arrive. When the current came, it slipped through the veil like a cool ribbon, and the polyps reached for its cargo.

Fishing gear had left marks on this slope too. People wanted to help the corals, but a good idea for land did not necessarily help in the depths. Above, on board, they spent a long time thinking and trying things out. The people even sent a striped parasol down into the depths. There were no sunbeams down here. They had brought everything they could think of for protection. A robot set up the pole beside the coral. Beneath the strange roof, water could still flow freely between the branches. A fish swam through while the people above were still thinking of better ways to help.

Many different substances entered the sea from human cities and ships. Some dissolved; others drifted on as particles. An extra covering was meant to protect the colony while still letting water and food reach its polyps. A green membrane surrounded a pale relative. Some particles caught outside; others slipped inside with the water. The polyps stretched their tentacles towards them. The protection could not become too dense. When too much dirt gathered at the edge, a helper had to remove it so the family stayed connected to the sea.

People could see the dark polyps only in their robot's light. Sunbeams did not reach their home. Danger here came from things such as heavy fishing equipment and changed water, not from a hot sun above the branches. Several very dark polyps sat in the orange middle of a pale relative. Beside them, a yellow one and a pink-and-yellow one could be seen. A little fish swam past so slowly that it seemed to inspect every branch. Then it moved on. Behind it, a dark polyp caught food while the others still waited in the water.

Dirt from human wastewater and fine clouds of sediment took turns at the reef. Helpers sought extra coverings for the delicate animals. The red cloak was one of these future ideas; food and fresh seawater still had to pass through. A green relative wore a red cloak. It followed every fork but left the colourful crowns free. Beneath it, the family lay as if under a second skin. A little animal felt along the edge, then vanished into the water again. The cloak did not turn the colony into another resident. It too needed the current and reached towards it each day with open tentacles.

Things people lost or threw away above gathered in the dark depths. Helpers even gave the family a large umbrella. Such an idea could deflect sinking pieces but could not shut out warming or dissolved substances. A large blue umbrella stood over a relative deep on the seabed. People had firmly anchored its pole. When loose particles fell from above, some slid past the roof. The umbrella could not help against the warmth of all the water. The colony knew neither sunshine nor rain. Yet its helpers named the roof as though it stood on a beach.

People had warmed the world over a long time. Warmer currents reached deep below too. Now helpers sought ways to save the family and even brought parasols down, although no sun shone here. Deep below, the family had been given a strange roof. Little parasols stood over the branches, though there was no sun here. Water movers turned underneath. Helpers cleaned the covering, and food lay ready at the base. ‘Slowly, one at a time,’ murmured the colony as its polyps opened. Even under this peculiar roof, everyone had to get something to eat.

During some work, a ship had loosened a lot of mud from the seabed. It drifted all the way to the corals. People now dreamed of little protective roofs, although no sun shone down here and the polyps needed open water. Little umbrellas now stood above some relatives. One pale colony had so many that hardly a branch was left without a roof. A fish swam between their stems. The yellowish polyps stretched into the water beneath the umbrellas. Their family had created new sheltered places, but food still had to arrive from outside.

People sought help against warmed deep water and thought of hot days on land. That was how an umbrella, glasses and cream entered the rescue fantasy. Below, the family needed cooler water rather than protection from sunburn. Deep in the dark water, a relative received a whole set of beach things. An umbrella, glasses and a tube of cream lay ready; a water mover turned beside them. People had brought familiar objects along. Above all, the family needed cooler, moving water. A few polyps stayed open in a little cave while helpers arranged their peculiar devices outside.

People brought their ideas of life on land into the depths. A hat and sunglasses looked strange there, since no sunlight arrived. Yet warmed water remained dangerous, and well-maintained cooling aids could help locally. A relative received a hat. Dark glasses, a handheld fan, a tube and a bottle followed. People arranged these around the colony, though no sun shone below. The family had no nose for the glasses either. But the little device moved water, and polyps reached for food passing between the strange objects.

Rubbish from cities and ships reached the dark reef. People tried to catch it before it reached the sensitive polyps. A diving robot brought material down and later took the full rubbish catchers away again. Above, on board, people grew long ribbons of seaweed in daylight. Later, a diving robot placed them at the edge of the deep reef as rubbish catchers. Down here, they could not keep growing. When rubbish collected among them, a gripping arm removed the ribbons again. Behind them, the pink coral kept catching food. The protection needed care and replacement.

People even designed a reflecting veil for corals far below the sunlight. In the deep darkness, it was an unusual rescue fantasy. Food and oxygen still had to arrive with water; a silvery shimmer could make neither. Tiny silvery partners floated above a relative. When a lamp passed, they shimmered like a moving veil. The colony gave some food to its little neighbours. When the current strengthened, they spread out and slowly gathered again. Then the unfamiliar light went out. The family stayed in darkness, waiting for its next meal.

People sought protective films for corals reached by fine particles. In the future story, a large polyp could spin a veil itself. Below, it protected against things in the water, not the sun; the deep sea stayed dark. A colourful relative spun a fine veil. A large polyp spread it over the branches until even the rear fork was covered. Loose particles caught on it and were shed again. The other crowns stayed free and caught food. When the current lifted the film, the spinning polyp patiently laid a new strip across the protected tissue.

People had allowed plastic into the sea in many ways. Some broke apart; other pieces remained as bottles or film. The green filter comb collected these pieces; only carrying them away cleared the family's home again. A green filter comb stood beside a dark relative. It caught drifting bottles and small pieces before they entered the branches. Soon the comb grew heavy. Helpers loosened the collected rubbish and carried it away. The violet polyps waited behind for their next meal. A filter only helped the family while its full contents were removed from the water again.

People found large pieces of waste even where they could scarcely reach themselves. The suction funnels were their fantastic collecting attempt for the depths. Bottles and tins were to be removed, not replace the family's natural food. The next relative collected rubbish with funnels. A bottle turned in the water, was sucked in and caught in a container. Then came a little scrap that a fish had nearly snapped up. The pink polyps did not have to deal with these big things. They caught their own tiny food while helpers lifted full collecting containers out of the sea.

People kept throwing plastic away even while rubbish was collected elsewhere. The imagined collecting mouths reached some pieces before they tangled in branches. This did not mean the family ate bottles; helpers had to remove the waste from the water. Long tentacles with round mouths searched for rubbish beside a pastel-coloured relative. One mouth snapped up a large piece while striped filters held smaller ones. Afterwards, helpers collected everything. Meanwhile, the polyps on the branches caught their tiny prey. So the family worked on two tasks at once: keeping its home clear and making sure nobody stayed hungry.

People had changed water in which calcium carbonate skeletons now struggled to survive. Diamond skin belonged to this deep-sea family's rescue fantasy. There was no sun for oxygen-making partners here; fresh seawater still had to reach the animals and let them breathe. A pink relative wore skin meant to be hard as diamond. Little lights sent signals to its neighbours, and fine scent trails accompanied the crowns. Room for water remained between the branches. The polyps took oxygen from it and caught food with their tentacles. Even the strangely hard protection could not do these two jobs for the family.

The damaged reef slopes offered fewer hiding places. Fish, crustaceans and corals met more closely on the remaining rocks. Some people kept fishing gear away from these places. The many protective ideas helped individual colonies. A whole reef also needed its neighbours. In this colony, the little animals were especially good at different things. One caught food even in rough water. Another lasted longer when little arrived. They were linked to the same body. So what helped one could help its neighbours too. In this way, a family grew in the reef whose members were not all alike.

Fishing gear had destroyed hiding places nearby. Fish gathered where branching colonies still stood. The water was dark as before, but room for so many neighbours grew scarce between the surviving branches. Four fish came through the green water. One stopped before the colony; the others turned and followed it between the branches. There was still room to swim through and hide. The coral did not count them. It only felt their movements ripple the water. After a long silence, something was happening in the family reef again.

Some nets had been lost on the seabed while people caught fish. People searched for them with diving robots so that no more animals would become tangled in them. The pale corals beneath had to be treated carefully during every recovery. A little fish stopped in front of a pale coral. From a distance, its polyps looked like little flowers. But whenever prey passed, the feeding arms reached for it. The fish flinched and swam on. No flowers grew in a flowerbed here. Many little animals lived together on a coral's branches.

People had learnt to consider the spaces between colonies when protecting the seabed too. Fish travelled there from one hiding place to the next. Heavy fishing gear could damage both these routes and their resting places. Two striped fish approached a pale colony. One swam around the left of the trunk, the other around the right. Behind the branches, they met again. Both stayed briefly in the calmer water there. Then the larger one moved on. The smaller one stayed a little longer before it too left its hiding place and disappeared among the stones.

People had heavily fished local fish populations. So it was noticeable when animals stayed at the reef again. Three fish did not mean the world was saved; their hiding places and food still needed protection. Three blue fish swam past a pale relative on the right. The first turned, the second followed, and the third had to hurry. They vanished behind the branches and emerged on the other side. The polyps swayed in their little eddy. Little had happened here for a long time. Now the current had company again.

Many fish hiding places had disappeared along with the damaged corals. So people protected whole pieces of reef as well as individual animals. Among their surviving forks, larger and smaller visitors could find different places in the same water. Several fish hovered before a pale coral with one blue polyp. One pushed between the branches, another stayed in front. A smaller one slipped deep into the fork. There was still room for it. When the current grew stronger, they turned together to face it. The coral gave each a different calm corner.

Many big fish had disappeared into nets in the past. Later, people limited the catch and left parts of the deep reef untouched. Coral branches survived there, along with the places where fish could swim past. Two big fish appeared beside a pale relative. They were much too wide for the gaps between its branches. They swam around the outside and kept searching along the seabed. The coral stayed in its place. Once the visitors had disappeared, the water brought small food again, just right for its polyps.

The depths were no place for people to swim freely. They studied the reef from submersibles and with robots. There, they saw fish, corals and the marks their heavy nets had left on the seabed. A diving robot stopped in front of the family reef. A big fish swam beside its camera head, while a shark passed further down. The pale coral stood among all these visitors. Above, on the ship, people watched its pictures. They kept the gripping arms at a distance. Only when the robot slowly moved on did smaller animals come close to the branches again.

Ships worked above the reef, but the seabed between these rocks had survived. People could spot different neighbours in their pictures. For all of them, it mattered that the current carried enough food into the dark habitat. A squid hovered on the left; a fish swam on the right. Below them, a small jellyfish drifted past, and a clam opened its shell on the bottom. The pale relative stood among them all. Nobody had to eat the same meal or take the same route. The current brought them together briefly, then carried little prey animals between the open polyps.

Far above the reef, fish were still being caught. Below, earlier nets had already destroyed some hiding places. In the protected remains, small and large visitors met among the few surviving branches. Several fish gathered before a pale coral. A little one tried to slip into the same fork as a bigger one. It was too cramped. It backed away and swam to the other side. There it found its own place. Above it, a colourful polyp and a dark one reached into the water and caught tiny food animals.

People now also protected bare stones beside the old colonies. They wanted to leave room for the young. Even so, the current carried larvae across the boundaries; not every little beginning landed in a suitable place. A narrow pink section began at a coral's blue base. Above it, the branches were pale green. A larva was carried close past them and landed on a bare stone. It stayed there. A new polyp had begun among the big branches. Many currents would pass over it before it could offer shelter itself one day.

Far above, people caught ever more fish and changed whole habitats. Below, only some reef sites remained undamaged. Shrimp, clams and fish crowded together there; enough food had to pass through the dark branches for everyone. Between the dark rocks, the neighbourhood grew without a single new branch. Shrimp darted past, clams opened their shells, and small fish vanished between green threads. Each species needed something different. Sometimes they helped one another; sometimes they got in each other's way. The current brought food. If enough arrived, everyone could find a meal.

Research pictures had shown that small fish used unassuming reef remains too. People included these places on their protection maps. For a fish, a hiding place did not need to be large, only the right fit between the branches. A yellow coral stood among the stones. A tiny fish pushed beneath its lowest branch. It fitted exactly. Above it, the fine tentacles drew back when its fin brushed them. Then everything grew quiet again. The fish stayed a little longer while the little animals above it kept catching food.

Fishing gear had left some reef sites flat and empty. Many animals sheltered at the remaining branches. People saw crowded pictures on their cameras, but also had to consider how much habitat was missing beyond the pictures. The green colony had many visitors. A large fish pushed its face between two branches; a little one followed, and a starfish lay below. For a moment, they looked like a curious audience. Then the large fish turned away, the little one hid, and the polyps kept catching food. Nobody on the reef had to wait for everyone to watch.

A camera shone its light among the dark rocks. Within the circle of lamplight, a little fish could see the larger visitor above it. Then the visitor's shadow moved on; later, the unfamiliar light above the branches went out too. In a research device's circle of light, a dark fish swam past a white coral with pink polyps. It stopped behind the trunk. A larger fish passed overhead. The little one waited until its shadow had gone. Then it came out and continued searching for food on the seabed. When the device moved on, the reef lay in darkness again.

People kept heavy nets away from a surviving piece of reef. Shoals of fish could still pass among its rocks. When research devices returned, their lamps briefly revealed the crowding in the otherwise dark water. A pale coral stood among fish and blue streams of water. A blue polyp sat on its lower branch. A shoal passed, and for a moment everything grew unsettled. Then the water's usual pull returned. A little fish stayed behind the trunk. It had found a quiet place while the others moved on.

An underwater cable ran along a rocky slope. People checked its route with a diving robot. It must not touch the pink branches, because a broken twig was destroyed far faster than a colony could grow back. A pink relative stood on rocky ground. A yellow-grey fish squeezed close past it, while smaller fish kept their distance. Behind a stone lay a bare patch. The water carried a coral larva there. It caught hold and stayed. Between the big visitors and the old colony, a new beginning had found room.

People had greatly reduced some fish populations and damaged other reef sites. Surviving shoals still sought hiding places. Where branches remained, fish and colonies crowded closer; the current had to pass between both. A shoal gathered before a relative. The fish swam close together, turned as one and briefly formed a wall. Behind them, violet crowns stayed open. A curious visitor waited for a gap. Then the fish moved on. The colony remained behind, its polyps waiting for the next small meal from open water.

A research ship had found fishing tracks at the edge of the reef. People placed the next protected area around the surviving rocks. Narrow spaces remained between the branches there, where little animals could escape the stronger current. A pale green coral with blue polyps stood in calm water. A tiny fish stopped before it. It was small enough to fit between the branches and was looking for somewhere to spend the night. Behind the wide fork, it found a place. While it rested there, the fine tentacles outside kept moving.

People mapped the relative with the green base before a cable was laid. The planned route passed close to the reef. With a different route, they could preserve the family's fixed home. Delicate green lay at the base of one relative. Higher up, the branches were pale yellow and pink. A little resident crawled along behind the trunk. A fish came from above, turned and swam on. Between these two routes, the polyps sat in their places. The family shared the reef with many neighbours, but each coral remained firmly in its own spot.

In many places, people had caught too many fish and damaged their habitats. Here, they left a section of reef in peace. Little fish could stay among the yellow branches while the corals kept catching food. Three fish passed a yellow relative. One was so small that it fitted easily through the branches. The blue polyps were not bothered by its visit. By the time it came out again, the biggest fish had long since turned round. The little one followed it. Behind them, the coral stayed in its place and kept catching food.

Fishing and damaged reef sites had changed the neighbourhood. Animals crowded around some surviving colonies. The pufferfish wall belonged to this invented community; it replaced neither food nor people's rescue of other habitats. Pufferfish puffed up around a colourful relative. Their spiny bodies made a peculiar wall. A visitor slowed and turned away. Inside, the polyps swayed in a narrow flow of water. After a while, the guards slimmed down again and swam apart. Protectors needed to find food too, and the family needed open routes to the current.

People had kept fishing gear away from a surviving section of reef. But there was still heavy traffic at the surface. What swam above could move on; below, the rooted colonies kept smaller spaces open for guests among their branches. A turtle swam past a pink coral. A fish darted around the trunk, and a starfish lay on the seabed. For a moment, it was crowded between the branches. Then the large visitor moved on. The little animals stayed. Each needed something different in the reef, yet they shared the same space.

After many fishing trips, the reef remains stood far apart. People wanted to preserve the hiding places that still existed. Between them, a little fish had to cross open ground before finding calmer water behind a trunk again. A coral with pink polyps stood among scattered stones. A little fish came in from outside and stopped behind the trunk. There it did not have to swim so hard. Later, it darted on to another stone. For it, the colony was a stopping place. For its polyps, it was the home they had built themselves.

People had expanded fishing and shipping, but had not reached every deep rock. Large and small fish still lived around the family here. Their little lamps belonged to this peculiar neighbourhood; no sunlight reached this place. Large fish swam around a colourful relative. Little lights dangled before their faces, and yellow rays filled the water. Below, smaller fish darted between two angular frames. The polyps stayed on their branches. Visitors could travel around the whole reef; the family had to wait for the current to bring food to this very spot.

Elsewhere, bottom nets had destroyed both corals and fish hiding places. So people closed this part of the seabed to such equipment. The dark, branching colonies remained among the rocks as a home for sea life. A fish with a large eye looked through two branches. A smaller figure disappeared behind the orange-brown trunk. Many sea residents met here. Some stayed only briefly; others searched the seabed for longer. The coral could not follow them. With its colourful polyps, it waited for whatever the current carried past.

A diving robot showed green areas on the lower trunk. Behind them, little residents of the dark sea were hiding. People protected the firm seabed from bottom nets so that the coral and its neighbours could keep their slowly grown homes. Green lay on the lower trunk of one relative, while the upper branches were grey-brown. Colourful polyps sat between them. A little animal crawled behind the base and stayed hidden there. Further up, water flowed past freely. The colony needed this open route for its food. Beneath it, the little visitor found a quieter place.

Fishing had taken many large and small animals from the sea. So people left certain sections of reef in peace. Among the surviving branches, little fish could still seek shelter when larger ones swam past. The shape of a large dark fish glided over the seabed. The little fish beside the green coral immediately disappeared behind a branch. It waited. Only when the large shape was far enough away did it come out again. Meanwhile, the pink polyps had caught their own tiny prey. In the family reef, everyone watched out for something different.

Where people had destroyed reef branches, fewer hiding places remained. Neighbours sought sheltered spots together. In this invented deep sea, a ray carried a whole relative while loose human waste still drifted past outside. A black ray rested beneath the next relative. In this strange world, the colony stood on its broad back. Little umbrella caps topped it, and a jellyfish swam past beside it. When the ray moved, the polyps swayed in the water. Together they stayed in a quiet spot until the current brought enough food for both neighbours.

When people destroyed the deep reef with heavy nets, fish and starfish lost their habitat too. So people protected whole sections of seabed. There, the green relative remained part of a neighbourhood that included more than corals alone. A starfish lay beside a green relative. Further up, several fish swam past. The coral carried blue, pink and orange polyps. Every resident searched for food in its own way. The starfish stayed on the seabed for a long time; the fish moved on. The colony waited in its fixed place until little prey came with the water.

People had surveyed the damaged reef remains and kept one area clear of fishing gear. Small sea creatures still found space among the surviving branches. The current linked their hiding places with the rest of the dark sea. Many little guests lived among the colourful branches. A fish darted past one side while a long-nosed animal drifted slowly along the trunk. Each found a different spot. The coral stayed fixed to the seabed. Its polyps caught food, and around it the reef grew a little livelier with every new inhabitant.

People had fished heavily in large parts of the sea. Later, they protected some deep reefs from heavy fishing gear. Where the branching corals remained, fish still found places between the seabed and open water. A fish with large eyes swam beside a yellow coral. It paused in front of the lower red part, then turned round. There was little room for it between the branches. Smaller residents came closer. The colony stood among all the visitors and opened its colourful polyps into the passing water.

People had destroyed some habitats beside the reef. Animals sought new hiding places among surviving branches. Their movements pushed a little water locally, but could not replace a great current bringing food and fresh seawater from afar. A small blue fish looped around a pale relative. It swam between the branches and emerged on the other side. Water moved in its wake. Some polyps caught the little particles drifting past. The fish sought a hiding place, the coral a meal. For that moment, their two paths fitted well together.

In many places, people had taken both fish and their hiding places from the sea. So little calm space remained among the surviving corals. Even one undamaged branch could give a small fish cover. A green branch was barely wider than the little fish. Still, a little fish found shelter behind it from a bigger one. It stayed very still; only its fins trembled. The yellow polyps above it caught food. Only when the big fish moved on did the little one leave its hiding place and swim between the next stones.

Fishing and heavy nets had made residents and hiding places disappear elsewhere. People changed the permitted fishing routes. The golden yellow colony stayed in its place, where little fish could still visit it. Several little fish gathered by a golden yellow coral. One swam up, one dived down, and a third stayed near the base. They spent a long time there. Then they moved on. The current found its way through the yellow branches and carried food to the polyps left behind.

Where people had dragged bottom nets over rocks, coral branches and fish hiding places were later missing. Here, a section remained protected. Different animals could still stay between the pink relative and the firm seabed. A big fish with a yellow edge swam close above the bottom. A pink colony stood ahead. It could not fit between the branches and passed around the outside. Smaller fish followed at a little distance. On the seabed, a larva caught hold of a firm stone. The family reef had a new, tiny resident.

People sought new helpers against warmer water and unreliable currents. The blue heat eaters were among these future inventions. In the depths, they too had to release heat; without a cooler current, they could not provide cold for free. Little blue residents sat on a pale relative's branches. The family called them heat eaters. In its peculiar future, they helped pass excess heat to cooler water flowing past. When the current stopped, helpers had to check. Even these little partners could not simply make heat vanish. The polyps waited until fresh seawater reached between the branches again.

A new protected area kept fishing gear away from the deep seabed. Sunken remains of coastal plants lay between the stones, but no seagrass grew down here. Fish and other animals still found little hiding places among the corals. Around the green coral, fish swam between stones and growth on the seabed. One little fish could not yet swim as fast as the big ones. When the water pulled harder, it settled behind a branch. There it could rest. Later, it swam out again. The reef offered many little safe places like this.

In a protected section, heavy fishing gear was no longer allowed to touch the seabed. Its narrow crevices remained intact. Octopuses and small fish found space there, while the corals kept catching food in their fixed places. A small octopus sat beside a red coral. It put an arm between the stones and felt for food. A fish waited at a distance. When the octopus crawled on, the place behind the trunk became free. At once, the fish slipped inside. The coral stayed where it was while the inhabitants around it changed.

People had protected part of the deep reef from bottom nets. The green coral remained standing there. No kelp forest had to grow around it: the branches themselves offered gaps for little animals in the dark water. Among a relative's green branches, there was enough room for small visitors. A fish darted through and paused behind the trunk. The pink polyps had spread their feeding arms. When food arrived, some caught it. The fish went on hunting. The colony stayed behind, rooted in the place its larva had once found.

People had stirred up parts of the seabed and lost nets. Yet animals still sheltered among surviving reef branches. A crab could live there as a separate animal and loosen threads; its eyes and claws were not suddenly inherited coral organs. Two eyes peeped from the sand beneath a pale relative. A crab had hidden there. When a thread caught on a branch, it pulled and snipped it through. Then it vanished beneath the colony again. With this neighbour, a cramped shelter became a useful shared home.

High up in the sea, tiny algae used sunlight to make food. Some of it later reached the depths as food for the creatures there. Human emissions changed conditions above, and below, the green coral waited for its meals. Pink and blue polyps sat on a light green colony. A little resident disappeared behind the trunk. At first, only its tail showed, then nothing at all. The current flowed through the branches. When the animal appeared on the other side, the polyps opened undisturbed into the open water.

An old trawl track ended near the reef. Beyond it, tall corals still stood because people had protected this part of the seabed. Among the surviving branches, fish found places missing from the bare track. Green branches and orange polyps belonged to a colony at the edge of the reef. A small fish let itself drift behind its trunk. The water was calmer there. It stayed still until a bigger fish had passed. Then it darted between two branches. The polyps briefly drew in their tentacles when it brushed them.

Through fishing, people had changed predators, prey and hiding places. A peculiar community arose among the remaining branches. The violet defence fish belonged to the future invention; they did not free the reef from needing food and a protected habitat. A green relative wore a fierce face. Small violet defence fish shot sideways out between its branches. A curious visitor preferred to turn away. Soon the guards vanished back into the colony's shelter. The polyps opened. Even in this well-defended corner of the family, the most important work only began when the current brought tiny prey.

People wanted to protect the rocky seabed better. Heavy nets were no longer allowed to touch it here. This preserved the firm place where the green relative and many little neighbours lived. A green colony had found room on a rock. Its polyps were orange, blue, pink and yellow. A little snail crawled along its base. It moved only slowly, but the coral stood much stiller. Above, a polyp caught a tiny crustacean. Below, the snail continued on its way over the stone.

Research pictures showed that fishing gear had struck more than just the corals. Their neighbourhood had changed too. Where people then left the seabed alone, starfish and other guests could still live among the reef remains. Starfish lay on the seabed around a red coral. One moved so slowly that a fish might have taken it for part of the ground. The next day, it lay a little further on. The coral was still in the same place. Its colourful polyps stretched into the water, which was always on the move.

People had caught animals and damaged many shelters. Neighbours lived more closely among the surviving branches. The invented cleaner polyps found visitors here; their special work did not change their need for food from the dark sea. A blue relative had adapted to small visitors. A fish held still while a pale cleaner polyp gently brushed along its side. Then it swam on. Violet tips marked the edge, and some crowns shimmered in darkness. The family's unusual work brought new neighbours. Yet even the busiest cleaners had to catch their own meals between jobs.

A diving robot showed people the green branches in the darkness. They marked their location on a map. No new cable was to be laid there, so that the colony's fixed home would survive. A rich green relative had grown slowly over many years. Its pink polyps now sat on large and small twigs. A tiny snail stopped beneath a side branch. Above it, food was being caught; beside it, water flowed past. Different animals lived close together in this way without having to take the same route through the sea.

People had learnt that a reef needed more than individual corals. They kept heavy fishing gear away and reduced fishing around it. Among the colourful branches, room remained for many deep-sea residents. There was a lot going on around one especially colourful colony. One fish turned between the branches, while another swam over them. For a moment, they almost met. Both turned aside in time. The polyps stayed in their places and caught small food animals. In this way, swimming residents and those fixed in place shared the same patch of the great family reef.

People had banned fishing with heavy bottom nets here. The blue branches were no longer torn off. Hiding places for little animals survived among them, although fishing continued out in the deep water. A little octopus felt its way over the seabed. Ahead stood a blue coral with yellow, pink and green polyps. It slipped an arm between the branches and stayed there. Small fish swam past. On this patch of the family reef, there was enough room for very different neighbours.

People imagined an inhabited house between deep coral branches. In the story, it became a tiny settlement. Its residents too had to leave room for polyps while human waste kept passing through the dark water outside. A relative had become a tree house. A ladder and little windows hung between its branches; a tyre swing dangled at the edge. A deckchair stood above. The tiny residents had built carefully, leaving the polyps free. When the current came, the washing swayed. Below, the coral kept growing, and sometimes somebody had to move a walkway to make room for a new branch.

After people closed a fishing area, the last tall coral branches there remained intact. Small fish still found spaces between them. The seabed lay far below sunlight; a green branch here was an animal's body, not an underwater tree. A green coral grew in a sheltered hollow. Its polyps sat on the branches like little colourful circles. A fish searched the reef for somewhere to rest. The hollow was cramped, but enough room remained behind the trunk. It settled there and let the stronger current pass outside.

Even later, people continued to interfere with the sea. In some regions, warmth and food arrived differently from before; elsewhere, firm places disappeared beneath mud. The family had to find a home for its descendants once more. In this distant, imaginary future, some branches found an unusual way out. Some of the family's polyps could now leave their places. With long arms, they moved through the water, almost like tiny jellyfish. Behind them, the pink colony remained. Ahead lay a cooler place. There, they searched for a firm spot. The travellers could grow into a colony again if they found enough food.

A bag had entered the sea from the coast and eventually sunk deep down. People above could no longer see it. Below, the same current that brought food to fish and corals moved it along. Two fish swam past a pale coral. Before them drifted a bag that billowed in the water. They swam around it and went between the branches. There was no lid and no pane of glass there. The way into the sea stayed open. Later, both left their hiding place and swam on over the seabed.

A heavy fishing net had broken branches behind the rock and stirred up mud. The walking fantasy relative could look for another place. The colonies rooted to the spot had to stay and needed protection from people's equipment. Some descendants could now do something amazing. A coral strode over the seabed on black legs. The water at its old home was no longer good for it. Slowly, it put one foot in front of the other. It stopped by a rock. Here, fresh seawater flowed through its branches, and it opened its colourful polyps.

As people warmed the world, water movements far below the waves changed too. Mud from seabed work joined them. Sometimes a dense cloud passed through the reef; the fixed family had to wait for it to go. This time the current came from the other side. Red, blue and orange veils swirled around a colony until its branches were barely visible. A small neighbour crouched behind the trunk. The polyps closed. When the water calmed, some mud lay on the rock, and the family first had to clear its tiny catching hands again.

Where people had worked on the seabed, much loose material remained. Water carried it elsewhere. At this reef, the base needed protection from sinking and the open polyps from ever more mud particles. The ground beneath a relative softened. Helpers put brown supports under its base and kept a small space clear around it. Water entered through holes. More sand kept trickling down from above. The polyps waited for the particles to pass. Then they opened again while somebody below checked that the supports still stood firmly.

People planned a new cable across the deep seabed. Camera pictures showed the unusually branching coral. The cable route was changed, because a descendant with a different shape also needed an undamaged place to keep living. Not all descendants had the same shape. In one relative, a red main branch ran diagonally through the body. Smaller branches pointed outwards and downwards. Water flowed between them. A polyp caught food in a place where other corals had no twig at all. This was another way the family could find room in the reef.

People had left marks on the seabed, with safe places far apart between them. In the invented future, this colony could walk away. It still had to find dark, cool water and food on its journey. A purple relative could do something its ancestors never could. Green legs moved beneath its base. When bad water came, it lifted itself from the seabed and took one careful step after another. An astonished fish swam alongside. The wandering family sought no great treasure. A place where it could calmly open its polyps again was enough.

People had changed a sea whose safe places now lay further apart. In this invented future, a colony could wander. The small thermometer helped it seek cooler water, not a route up to the sun. A pale relative set off. It followed cooler water, very slowly, while a small thermometer confirmed the direction. The family behind stayed on the old rock. This wanderer had no quick leap to its destination. It stopped again and again to open its polyps. Even on a journey, there had to be enough time for a meal.

Above the sea, the weather changed as people brought more and more heat into the world. Below, measuring instruments recorded how the water varied. The depths felt no gust of wind, but their currents did not stay the same. A storm raged above the sea. In the reef too, the water pulled harder. The pale coral stood firm, but many of its polyps had withdrawn. A small fish pressed behind a stone. When the current eased, it came out. On the branches, the pink tentacles gradually opened.

People developed devices to loosen rubbish on threatened deep reefs. It then had to be collected, or one large piece simply became many smaller pieces of waste. Meanwhile, the wandering fantasy colony sought routes between polluted rocks. A pink relative walked across the seabed on small feet. A blue shield hung at its side. Red cleaning beams loosened trapped rubbish, which helpers then collected. Alone, the job would have stayed unfinished. With hand-like tips, the colony kept in touch with its neighbours. Step by step, they sought a place where enough fresh seawater flowed between the rocks again.

People had damaged seabed areas between which firm rocks still rose. In the invented future, Super Bernt could climb there. The cape and goat's head were no result of a coral's wish, but part of this unusual deep-sea story. Super Bernt was an unusual relative. A yellow goat's head sat above turquoise branches; red limbs stretched below, and a cape streamed to one side. Bernt climbed carefully along a rock. A little shrimp stayed between the polyps. When both found a quiet ledge, they stopped. Even a goat hero had to give the family time to eat.

People placed current meters on several sides of a rocky ridge. They wanted to know which route the food took. Below, small swimmers had to find a new calm corner whenever there was a stronger change. The water did not come from the same direction every day. Colourful polyps sat all around a pale coral's branches. When little passed one side, the other sometimes received more. A fish kept having to change its quiet place behind the trunk. The little coral animals stayed where they were.

People marked deep reef sites so their devices could find them again. A dot looked small on a map; below, a whole family stood there. A lost net or nearby seabed work could still damage several generations of its home. A little flag waved beside the turquoise-green relative. People had marked the place to find it again. The polyps needed no sign. They stayed on the rock and reached into the current. When helpers returned, they discovered a small new branch. They moved the marker a little further away so the family had room to keep growing.

People had broken the seabed in some places and left old objects elsewhere. New shelters formed among little pieces. Not every remnant was useful, and none automatically promised food; the family had to manage with the arriving water. Three differently coloured pieces lay beside a pale relative: one dark, one yellow and one green. The current had deposited little things around them. A tiny resident hid behind them, emerging only after a larger fish left. The colony stayed on its rock. Sometimes new neighbours needed only one small extra edge to find room in the family.

People threw away little things they barely missed. A cigarette butt could drift far and later catch on a deep reef. Below, the waste reached animals that knew nothing of its origin and could not simply avoid it. A cigarette butt drifted beside a pale relative. A little fish snapped at it and immediately let go. The current pushed the butt between two branches. It did not belong there. When a helper spotted it, it was carefully removed. The polyps could stretch out again, but the water still carried other human traces.

On the research ship, the people saw how much the currents near the seabed varied. They checked where new work would have to keep its distance. Food came along the same routes that could carry stirred-up sand all the way to the colonies. A strong current swept past one colony. Red, yellow and green covered its upper branches. A little animal was caught by the water and drifted along them. Fine tentacles reached out and caught it. Below, a fish stayed behind the trunk. Only when the current grew weaker did it venture out among the stones again.

Heat from the human-altered world reached deep reef sites with the water too. People measured the danger and helped locally with cooling. The drawn suffering face showed distress, not an ability for coral to sweat underwater. Water seemed to shimmer around the next relative. Its little face looked tired. The polyps stayed withdrawn longer than usual. A helper held an instrument beside it and called the others. They brought cooler water into the small shelter. Slowly, one crown stirred. The family needed help long before it could have a peaceful day again.

People tried to help deep colonies with food, care and small devices. Between visits, rubbish kept arriving from the inhabited world above. The family shared its branches with fish seeking shelter. A little fish vanished between rainbow branches. Moments later it peeped out somewhere quite different. The colony offered many hiding places. A fan stood beside it; food and strange care tools lay below. There was even a toothbrush. The helpers laughed when they found it, then set to work keeping the protected place clean.

People had placed current meters at the edge of the reef. The instruments showed strong and weak movements of water. Through these changes, the family had to reach food; loose rubbish lost above, meanwhile, could catch on their long extensions. Some descendants bore long red and pink fans. The current pushed them sideways. Tiny food particles caught between them. When the water suddenly pulled harder, the soft fans folded against the body. A fish rushed past. Only when calm returned did they slowly spread out again.

People could now visit the depths with diving equipment and sometimes came too close to animals. This special colony answered with light of its own. Above, visitors had to learn that even a well-meant visit needed distance. A visitor in a heavy pressure-resistant suit came too close to the relative. Suddenly it shone yellow and red. This glow existed only in this invented family story. Behind the visor, the visitor paused and stepped back. Only then did the lights fade. Between the branches, the polyps moved calmly again. This time the person kept a distance.

On land, people decided how to treat distant deep reefs. Their votes changed no polyps, but did change rules for fishing gear and interference. A decision could preserve space below, though nobody there needed to understand a ballot paper. A vote took place on land. People decided whether an area of seabed should be protected. Far below, a pale relative stretched out its polyps. It could not cast a ballot. But a few days later, heavy fishing gear stayed away. The current kept bringing food, and a small new polyp found room on an undamaged branch.

In the pictures from their diving robots, people saw how many reef sites were being lost. Some tried to save the remaining colonies. They built shelters, moved water and brought food. At the same time, habitats were still being damaged elsewhere. One rescued branch did not make a healthy sea, and every device needed care. People had fitted a little device beside a pale relative. Thin tubes led to the branches. Carefully, they checked whether everything was still secure. A fish approached, turned and swam on. The people kept their distance. They watched the polyps for a long time, because a coral could not tell them what it needed just then.

People had installed devices to help at the deep reef. They checked them with diving robots, because people could not simply kneel here and swim away with flippers. Even helpful gripping arms had to keep their distance from the sensitive branches. A little box stood at the base of a pale relative. Fine lines ran from there to the branches. A diving robot's gripping arm checked the connections. Above, on the ship, a person moved it very slowly. It had to stay clear of the trunk. Then the robot moved back, and the polyps kept waiting for food from the dark water.

In this future, people built small supports beside a surviving piece of reef. They did not want to tear up any more seabed. Thin lines were meant to secure a new place so that the next strong current would not shift it again. Thin lines ran around the base of a pale colony. They were fastened to round supports and held the new place to the seabed. When the current pulled harder, they grew taut. A little fish swam between them. The coral stayed standing. Its polyps reached the water above the seabed and began to feed.

People developed an imaginary protective spray because their own actions were putting the corals in danger. A diving robot brought it into the darkness. At the same time, they had to keep rubbish and heavy fishing gear away; a spray could not do those jobs. There was a special protective spray for a delicate pink relative. People applied it carefully and left the open polyps clear. A thin layer remained on the body. Then the helpers moved back a little. The coral had to be able to keep catching food. Its protection was useful only if its daily life still worked with it.

Substances from factories and emissions had caused pollution that reached the deep sea. People searched for a special protective cream for corals. This was a rescue idea for the darkness, not sun cream against real sunbeams in the deep sea. People were also looking for help for the family reef. They developed a special protective cream for a pink relative. Carefully, they applied it to the branches. The polyps needed to be able to keep catching food. Then the people waited and watched the colony. Helping took patience and had to suit the animal it was meant to protect.

Fewer plastic bags on land meant fewer new pieces that rivers could carry into the sea. This did not remove rubbish that had already sunk. People also had to search for it without breaking the deep corals. Even far from the reef, people helped decide what reached the water. Some stopped taking a new plastic bag when they went shopping. Others collected rubbish on the beach. Below stood a green and pink relative with colourful polyps. It could not carry a rubbish bag. People had to do their own share of the work.

Because people had warmed the climate, they searched for technical ways to help the depths. In their rescue fantasy, pipes led to a cool room. This circuit needed care; a few pipes could not cool the whole sea. Long pipes now ran beneath part of the reef. Warm water flowed in and was led through a cool room under the seabed. Afterwards, it returned to the branching coral. Red and blue showed the route through its unusual home. In this place, the family depended on a whole circuit that had to keep working.

The sea had absorbed a great deal of heat. People searched for every possible way to help the remaining colonies. More and more objects came down with the robots. But no toolbox, however full, could bring back the lost habitat by itself. People had brought everything they could think of against heat: a parasol, ice cubes, a cream and even a cooling plate. Robots took the things down to the pale coral. Sunbeams did not reach this place. It was an exaggerated rescue idea from the world above. Above all, people had to keep checking whether their devices helped and whether enough food passed the polyps.

People kept releasing carbon dioxide into the air. Some entered the sea and changed the water in which corals built their skeletons. A protected area kept fishing gear away but could not stop this change alone. At last, people drew a boundary on their map. No more nets were to drag over the seabed in this part of the sea. The pink and yellow colony knew nothing of maps. It only noticed that its branches stayed standing. That did not make the water good again all at once. But its youngest polyps gained time to keep growing beside the older ones.

People searched for ways to help reef remains where fresh seawater passed less regularly. Now they built a wheel into the current. It was meant to move water without laying a new heavy pipeline through living branches. Beside a colony, a wheel turned, driven by the flowing water. It moved a small fan. As soon as the current arrived, the fan stirred the water between the branches. A fish kept a curious distance. When the water stopped, the wheel stopped too. Then the polyps waited for food, just like their relatives outside.

Images from the depths appeared on screens on land. A child recognised the same colony again and again and gave it a name. This also helped people notice when a net later lay beside the familiar place. A child named the green relative Bobbler. On the next visit, the child looked for that very fork and the pale crowns. ‘There you are.’ A fish swam between the branches. Bobbler could not answer. But the child remembered the place, and when a net later lay nearby, fetched help.

In pictures, people saw what their fishing gear and waste did below. Some changed rules and explained why the depths needed protection. Such decisions kept harm away while corals continued catching food from the water. Above the reef, people began listening to one another. They learnt, passed on explanations and stopped doing things that hurt the seabed. Below, the pale colony opened its tentacles. It could neither eat hope nor drink respect. But when words became careful hands, its family gained something very useful: time and a place where it could keep living.

People could not cool the warmed world again at a stroke. For individual colonies, they tried cold supplies and devices. Deep below, this helped only locally, and only while energy and care kept coming. People arrived with a fan and a supply of ice. They wanted to cool the little pool around the colourful colony. The fan pushed water between the branches; the ice melted slowly in a container beside it. A polyp opened again. The helpers stayed and checked the temperature, for saving this afternoon did not yet mean saving the whole sea.

People even brought things from their own everyday safety into the rescue fantasy: a helmet, vest and fire extinguisher. Below, it remained dark. The real dangers came from damaging equipment and changed seawater, not from a fire in the reef. One relative had very special equipment. It wore a helmet, a safety vest and little goggles. Beside it stood warning signs, a glove and even a fire extinguisher. A fish looked at everything and swam cautiously on. People had brought many things for protection. Even so, the polyps still had to keep enough room to eat.

People placed cold supplies beside protected colonies. A current carried water past them. Cooling needed replenishing, and helpers had to check regularly that the water remained suitable and every polyp could reach its meals. Blue cooling containers stood beside a grey relative. Water flowed past them, then between the branches. The colony stayed grey; nobody needed to restore its colour. What mattered was whether its polyps caught food. A helper bent over the display and nodded only after seeing several little tentacles moving below.

People maintained cooling stations for individual deep reef sites. A boat brought supplies; pipes carried cooled water down. The system needed servicing; this small rescue did not make the surrounding dark sea cold again. A little boat brought fresh ice to the cooling station. The pink relative below could neither see the boat nor know how much work was being done. It only felt the flow from the sheltered pool. Above, helpers replenished supplies and checked the pipes. If they stayed away, the water grew warmer again. At this place, the family depended on their regular visits.

Heavy fishing had damaged the open reef. So people built cared-for shelters in the depths. There, they had to keep an eye on water movement and food; a solid frame alone did not make a good home. Some people built a sheltered place with a firm border for descendants of the family reef. A coral and little fish lived inside it. The people checked the water and made sure food arrived. Life went on behind the frame. But the colony needed their help every day, even when everything looked peaceful.

People took some descendants from the depths to cold tanks on land. They lived in captivity there. Pumps, food and care now had to replace what their family usually received from deep currents. People now even brought some descendants onto land. There stood a tank beneath a transparent bell. A pink relative lived inside in cold water. Outside, the sun shone on sand, and a bird flew past a tree. A child laid a hand on the cool wall. The coral stayed still. Its polyps waited for the little water movement a pump would soon start again.

Warming caused by human emissions affected the deep sea too. People sent equipment down and searched for cooling and protection. Their rescue fantasies were meant to help the polyps without blocking the food-carrying flow needed between the branches. When danger came, a blue relative could pull in its polyps. Then very little of its colourful feeding arms could be seen. People also helped it with cooling and a special substance in its tissue. Carefully, they waited until the polyps opened again. Only when small food animals were caught did they know: the coral was eating again.

People sent instruments into the depths on long cables. They wanted to know how temperature and water were changing. The little bot could deliver messages; food and a useful current still had to reach the family on its rock. A black cable ran beside a pale colony up into its crown. A little bot waited below. It stirred when its helpers on land wanted to know something. The polyps knew nothing of its questions. They caught food while round instruments hung in the water. Sometimes after a reading, a person came, checked the branches and stayed completely still for a moment.

Fishing boats had not recovered all their lost nets. Some remnants dragged across the seabed for years. People had to remove trapped lines carefully; a protective rim alone could not retrieve waste from the depths. A net slid over the edge of a protected colony. Points outside caught its line. The branches behind stayed free. But the net would not vanish by itself. When people returned, they cut it loose piece by piece. Only then could the current reach the little open crowns inside without obstruction again.

People wanted to save more than individual branches. They kept fishing gear away, collected rubbish with gripping arms and reduced pollution on land. In this way, their wish to protect nature reached from the cities down to the dark family reef. People wanted to protect nature better. So they looked not only at the corals, but also at what they themselves brought into the sea. By a yellow relative, they kept their distance from the blue polyps. They collected rubbish all around and left the branches in peace. Here, helping began with their own hands and their own decisions.

Ships lost things that sank into the depths; warmer currents arrived too. People therefore combined several rescue attempts. The umbrellas seemed like a strange greeting from the beach, while water movers and food supplies truly needed maintaining. Three umbrellas arched over a pale relative. Little rotors pushed water between the branches, and food supplies lay beside cooling blocks at the base. The family was ready for a difficult day. When the current weakened, helpers shared a little food. Not all at once: even the smallest polyp on the furthest branch should get some.

Plastic was thrown away on land, and equipment was lost at sea. Some sank all the way to the corals. So people had to create less rubbish and use diving robots to recover what had already become caught in the reef. Rubbish was drifting above the family reef again. A diving robot's gripping arm picked up a piece before it could catch among the branches. Above, on the ship, people guided the help. They also wanted to stop new rubbish from reaching the sea. Below, fish swam past a colourful coral. People had to clean up carefully and keep helping on land.

Warmer currents reached the dark slopes too. People therefore stored cold water in protected spaces. Cooling remained a job needing pipes, energy and replenishment, while the wider sea flowed on unchanged outside the covering. A supply of cold water lay beneath a clear covering. Above it, a water mover gently washed around the pastel-coloured relative. A robot opened a valve with its gripper, and a cool stream reached between the branches. The polyps stretched out. For a while, the space was supplied. Then somebody had to refill the store before it ran out.

People supplied individual protected colonies with food. A fence kept large visitors away but made the enclosure tighter. Helpers had to ensure enough water circulated and food reached even the furthest polyps. A fence surrounded the next relative. Food lay ready below, and a fan moved water above. A fish stopped before the posts, then sought another route. Inside, a helper shared small portions between the branches. The polyps reached for them. However well sheltered they were, their meals still had to arrive at the right branch at the right time.

People could harm the deep corals with fishing gear and careless gripping arms. So they set limits for their work. The warning signs were part of this human idea for protection; the dark sea itself did not stop anyone. People were to keep the reef clean and leave its residents in peace. A special bubble helped with this by one colourful colony. If a piece of equipment came too close, it gave a loud sound. Above, on the ship, people heard the warning and pulled back the gripping arm. Afterwards, they kept their distance and watched the polyps only with the camera.

People had combined different protective ideas at one reef site. A dome, ribbons and pipes made a small installation. Since dirt kept arriving from the inhabited sea, helpers had to return to the depths, empty filters and check water exchange. A blue dome arched over a pale relative. Green ribbons crossed the space below, and dark strands led to the seabed. Helpers had assembled several protective ideas. The polyps lived among this equipment, waiting for fresh seawater. When a filter filled, somebody carefully removed it. Then the little current flowed freely to the rear branches again.

The help gave some colonies time. But the sheltered places remained separate from one another. Between them lay damaged slopes, dirt and unsuitable currents. Other branches of the family lived far from the helpers. Their bodies now carried many different forms of protection, small and large. Fine round borders ran around the polyps of a pale relative. A little fish came so close that it had to turn in front of one. Then it kept searching under a branch. The coral stayed firmly on the seabed. Its polyps stretched feeding arms into the water and caught food while the visitor found a new route through the reef.

People had changed the water and seabed all around. In their ideas for the future, a coral was therefore given a stern face and unusual defences. This did not stop emissions on land; people had to deal with those themselves. One pale relative looked especially stern. With big eyes and an unusual defence, it could frighten visitors. A little fish made a detour just in case. Pink extensions reached beneath its base. Between the branches, room remained for food from the current. Even this well-defended coral had to eat in order to keep living.

During work on the seabed, people had stirred up fine mud. A layer of slime was part of this relative's imaginary protection. Even so, the extra source of dirt had to stop so that the polyps could keep catching food from the water. A pale relative had a smooth layer of slime around its body. It looked like a snail's trail. When fine grains reached the branches, the layer lay in between. The polyps kept stretching their feeding arms into the water. A little fish slipped past. The coral stayed firmly in place and caught whatever passed close enough.

After many reefs were damaged, more and more open ground lay between the last hiding places. People had not been able to protect every colony. Hungry visitors now pushed right up to the branches, including the dangerous tiger flowers of this future. When tiger flowers came into the reef, the polyps drew their colourful lightsabres. Little blades flashed everywhere. The intruders stopped and went around the colony. Only then did the tiny guards put their swords away again. Between the branches, all grew quiet. The next current brought them food rather than enemies.

Some carbon dioxide from power stations, traffic and factories entered the sea. This changed the water in which corals built their calcium carbonate skeletons. People dreamed of a protective layer, but at the same time they had to reduce their emissions. A pale relative carried a thin protective layer. Small patches on its body released special substances into the water. This helped it cope with changes right beside its branches. A fish swam past without noticing the patches. The polyps stayed facing outwards. Even this unusual coral needed food from the surrounding sea.

Elsewhere, more and more pieces of reef disappeared beneath fishing nets. The animals that remained gathered in less space. Hungry visitors now also came right up to the soft polyps more often. This coral was hard to spot in the blue water. Its colours matched its surroundings. When a hungry visitor approached, a polyp stretched out its long stinging thread. The visitor backed away. Between the branches, all stayed quiet. There, the smaller polyps kept catching the tiny prey animals that came with the current.

Fishing gear had destroyed large parts of the old reef. More and more inhabitants sought out the hiding places that remained. There, the soft polyps more often met hungry visitors pushing between the branches. Pink spines grew on a dark coral. When a hungry animal came too close, it had to pass between the points. It turned away and searched elsewhere. The orange-yellow polyps opened again. Tiny prey animals caught on their tentacles. The trunk looked dark, yet in the reef it was full of life.

Human emissions were changing the water even at deep reef sites. The layer of slime was an imaginary way to help with these changes. It gave nobody a reason to keep releasing emissions or to think every temperature was harmless. A layer of slime surrounded an orange relative. This special covering was meant to make rapid changes in the water easier to bear. The pale polyps stretched their feeding arms outwards. A small prey animal became caught. Other descendants of this line found new places in the sea. But each of them still needed good water, food and a place to attach and grow.

For a long time, people had damaged parts of the reef with heavy nets. Where branches remained, many neighbours now gathered. For the soft polyps, having everyone so close also brought hungry visitors squeezing into the last hiding places. A hungry fish searched among the stones. Ahead of it stood a colony whose colours blended into its surroundings. It swam past without discovering the polyps. They stayed still until it had gone. Then they stretched their tentacles into the water again. The current brought small prey animals for which they needed no hiding place.

More and more animals crowded among the reef remains that fishing gear had made smaller. People protected individual rocks, but they could not magically create empty spaces. There, some residents helped one another guard the branches that still survived. A little guardian fish swam around a green and violet colony. When a hungry visitor arrived, it confronted it. At the same time, the coral released foul-smelling bits of skin and changed colour. The visitor moved on. Beneath a protective layer of slime, the polyps opened again. The little fish returned between the branches, where it found shelter itself.

In some parts of the sea, people worked with heavy machinery. Small stones and hard rubble were loosened in the process. When currents pushed these pieces towards the reef, they met delicate tissue between parts of a firm skeleton. Hard dark rings lay around a colony's branches. When a little stone struck the body, it hit one of these rings. It fell to the seabed. The soft polyps beside it had withdrawn. After a while, they opened again. Their new rings did not keep everything away, but this knock had turned out well.

A diving robot showed people little figures beside the pink coral. At the same time, they found rubbish on the seabed. They had to work carefully so that recovering it would not frighten the animals and damage the slowly grown branches. A little figure moved beside a pink relative. A dark dot drifted close past the trunk and disappeared into the water. Some polyps drew in their feeding arms at the touch. Later, they opened again. The colony stayed in its place. Whatever could swim moved on; whatever was fixed waited for food from the next current.

Fine mud from human work had reached some reef sites. On land, people searched for better ways to work without stirring up new clouds. Below, the family still depended on clear water between the next surges of dirt. A blue covering lay around the golden branches, soft as a transparent bubble. The water moved more slowly inside it. When fine sand passed outside, some caught on the covering. Later, the edge came loose and drifted away. Beneath it, the polyps could reach the water freely again.

People dreamed of an armoured coral because heat and heavy interference threatened the reef. Its armour was meant to help in the depths. People still had to protect it themselves from bottom nets and the constant warming of the whole sea. A yellow relative wore armour. It absorbed heat for a short time and grew warmer itself as it did so. Chains held its body to the seabed. The pink polyps stayed facing outwards. A strong flow of water arrived, but the anchoring held. Small food animals were carried past. The armour helped this coral, but its many little residents still had to eat for themselves.

Heavy fishing equipment had broken other colonies. For this fantasy relative, people imagined angular protective pieces. But its home only became truly safer once nets were no longer allowed to drag over the seabed there. Dark, pointed protective pieces sat on some twigs of a pale relative. Beside them lay broad shield-like shapes. A little fish kept its distance just in case and swam around the outside of the colony. The polyps opened among the protected branches. They did not have to chase anyone. The water brought tiny food animals close enough to their feeding arms.

People built ever stranger defensive devices around threatened reefs. They wanted to keep attackers and fishing gear away. But weapons changed neither the water's temperature nor its food; the family still needed suitable living conditions. In a remote corner stood a relative with pistols on its branches. It looked frightening, and small fish kept their distance. But when warm water came, not one weapon helped. The polyps stayed hungry. Later, people disabled the devices and brought a pump. Only its quiet flow achieved what all the noise had failed to do.

Technical barriers grew around some deep reefs. People used them to keep their own interference away from colonies. Every device needed maintenance, and every grille could catch new rubbish until the current struggled to pass. Cannons and a fence with yellow lightning bolts surrounded a blue colony. A warning sign kept visitors back. Inside, the polyps waited for tiny prey. The current had to find its way through the installation. One day, rubbish caught on the fence. A helper switched everything off and removed it before it blocked the entrance.

Lost fishing nets kept drifting through the depths. People above had long given up on them, but below they still became tangled. Even the strangest rescue equipment ultimately had to help free a line from delicate branches. A hammer lay beside the next colony; yellow and blue lightning flashed above it. On the left, the current brought a net closer. In this corner of the sea, even thunder tools belonged to the rescue equipment. The hammer pinned the net to the seabed until people freed it. Then peace returned, and the colourful crowns could stretch out.

People sought images for protection and escape. Even for the deep sea, they imagined shields, swords and shoes. Yet the family lived among real dangers: nets could snag, water could warm and food grow scarce. A relative had a shield, sword and even shoes. When a fish darted between its branches, the shield wobbled a little. But the shoes were meant for another day: the day it had to leave. For now, it stayed. The current brought food here, and no heroic deed seemed more urgent than feeding the family's hungry polyps.

The black shields were part of a rescue fantasy for the changed sea. People had contributed to warming through their emissions. They had to keep reducing the cause instead of only fitting more and more protective pieces to corals. Black shields lay on the branches of another relative. They were meant to protect its body against changes in the sea. Between the plates, the polyps remained free. A little fish swam along the outside and searched for a gap. The coral could not eat its shields. Even behind this protection, it still needed food and fresh seawater.

In people's pictures, a coral even received a hero's cape. Below, everyone still had to work together. Neither a crest nor a single colony could deal with what sank from cities and ships. A red cape spread behind a pale blue relative. A crest shone on its trunk. The small neighbours called it their superheroine. But when rubbish came, even she could not carry it away alone. A shrimp pulled a thread, a person lifted the large piece, and only together did they clear the way to the current again.

People enclosed protected places with ever more fences and coverings. The green hedge was one such rescue idea, not a plant finding sunlight below. Its entrance had to stay open for small neighbours and flowing water. People had placed a green protective hedge around the red colony. Only at the bottom was an entrance left open. A little fish found the gap, swam in and straight out again. The current took the same route. The family had gained a sheltered courtyard, but the opening mattered as much as the dense boundary. Food and new neighbours arrived there.

People built unusual boundaries around deep reefs to protect them from interference. Here, a thorny hedge and popping fruits belonged to the invented defences. The light came from the special colony; no sunlight reached this place. Suddenly, it grew bright behind the next hedge. The colony sent yellow rays out between its branches. Red fruits sat along the green edge; anyone bumping them heard a startling bang. A little fish made a wide detour. When all was quiet again, the family remained alone with the current winding through the dangerous garden.

Fine particles from human interference reached every side of the colonies. A protective layer therefore could not cover only one side. The green coat protected against things in the water, not rain, which never fell deep below anyway. A relative wore its green coat closely around its branches. An entrance remained at one side. Small visitors darted inside, followed by fresh seawater. The coat did not rustle as on land; it moved softly in the current. Beneath its protection, colourful polyps opened, each with room for its tiny feeding tentacles.

People had changed the climate and wished for an invisible shield for the corals. In the deep water, this became a rescue fantasy. Reducing emissions and destructive fishing nevertheless remained tasks in their own world. An invisible shield surrounded a dark green relative. A fish could not see it and swam curiously around the branches. The coral stayed behind it while the water changed outside. A pink polyp opened among the pale ones. Even in shelter, it was still hungry. The shield could not replace its food.

People built shelters around threatened reef remnants. They also made defences that blocked other animals' paths. A trap and a cloud of substance belonged to the invention here; they could secure the space while keeping new neighbours away. A trap lay at the next shelter's edge. Red points faced outwards, and a small defensive cloud escaped on the other side. A fish preferred to turn back. Inside, the pale relative stayed behind. The current now needed a detour to reach its polyps. When food finally arrived, everyone reached for it; they had waited long enough.

People had built walls beside the family to protect it from interference. But solid walls could narrow the water's path. A rescued colony still needed room for new branches and food from the dark current. A wall stood on the left, a wall on the right. Between them grew a colourful relative. Its branches almost reached the stones. A small fish still fitted through; so did the current. Helpers studied the cramped space and later moved a stone. Protection should leave the colony room to live, especially when a new branch grew.

People placed protective frames and cooling aids at individual reef sites. Outside, dangers were meant to catch; inside, water had to circulate. The more rubbish arrived from nearby, the more often helpers had to check below and carefully clear up. A pointed frame surrounded the next family branch. Narrow paths between its red joints led inside. Blue cooling blocks lay there beside colourful branches. A helper carefully opened a flap, removed dirt and closed it again. The polyps moved in fresh seawater. Even the strongest frame needed someone to care for the small space behind it.

People surrounded some deep colonies with ever more elaborate protective systems. Metal, a bell and devices were meant to keep their own interference away. Yet the installation needed energy and care; inside, the protected polyps still had to reach water and food. A darkly armoured relative stood beneath a clear bell. Green lines crossed the space; small defensive devices sat along the outside edge. People had built much around the family. Inside, pale polyps remained visible. A helper switched the devices off, opened a flap and checked the water. Among all the technology, the coral still needed room to live.

In some places, people now created little water worlds around the last colonies. They kept food, temperature and current within useful limits. This had not repaired the open sea outside these spaces. The family's question was still the same: would the next little corals find a home too? A transparent dome stood over a colony. Small wheels at the sides moved water between its branches. Outside, a fish passed by and turned back once more. It could not swim through the wall. Inside, the polyps opened their tentacles. People now had to make sure that food came in with the fresh seawater too.

People wanted to save individual colonies from nets, rubbish and careless visitors. They built shelters and had to return to the depths again and again. Outside, the sea remained changed; inside, the family constantly needed fresh seawater. People built a protected space for a colony. Nets and rubbish were to stay outside, visitors to keep their distance. There was even a tiny shop below. Inside, the family stretched out its polyps. The roof alone did not make water cool and clean. For that, helpers had to return repeatedly to measure, repair and carefully check everything was well.

Fine waste from human cities and ships reached the depths with the current. Clear coverings now surrounded some colonies. They were meant to keep dirt away without blocking the vital route for water and food. An almost invisible bubble surrounded the next relative. Behind it lay green, yellow and violet branches. A drifting particle slid along the edge and on. But the bubble let a narrow current inside; otherwise the sheltered space would soon have been eaten bare. The polyps stretched towards it as though reaching through an open door.

No firm boundary lay between the cities above and the reef below. Small plastic scraps arrived with the water. People tried to give individual colonies a clear shelter; outside, the waste still needed collecting. A pastel-coloured relative stood inside a barely visible bubble. Outside, a little piece of plastic drifted past and briefly caught on the edge. Then the current took it away again. The polyps inside slowly opened. Their pale colours said little about their hunger. Only their tentacles' movement showed it when the next small meal arrived.

People had tested many coverings that tore or became dirty. In their rescue fantasy, this bubble was finally meant to last. Inside, the family still depended on food and water arriving from the dark sea. A violet bubble enclosed the next family branch. In this story, it could not burst. A drifting stone hit it, slid along the edge and fell down. The colourful branches remained untouched. Yet food still had to enter. The current came through a small opening, and the polyps waited there until a new meal reached their tentacles.

People wanted to protect a pale colony from changed water inside a covering. They supplied this little place with equipment from a submersible. Outside, they still had to limit their actions instead of simply enclosing individual animals. A pale relative lived entirely inside a covering. Fish swam past outside, while inside, the branches stood still. People had to make sure fresh seawater and food got in. The polyps opened as soon as prey reached them. Whoever had built the covering must not forget the coral inside. Its life went on every day.

People kept throwing rubbish away while others helped the deep reefs. Cigarette ends and plastic reached the very shelters that had just been so carefully cleaned. Keeping a place clean was therefore a job that began all over again, time after time. Outside, cigarette ends and rubbish drifted past. Inside, a colourful relative stood in her protective bubble. Small blue cooling blocks were dotted all around. A helper collected the rubbish first, then checked the covering. The polyps waited patiently. It was easier to remove a harmful object in time than to free every single fork in the branches from its tiny particles later.

People were now cooling small sheltered spaces on the deep seabed. Bubbles and clear coverings were among their strange experiments. The equipment needed power and fresh supplies; all around, the family remained connected to the changing sea. Transparent bubbles floated around a colourful relative. Cooling blocks lay at her base to cool her sheltered patch of water. One little bubble broke free and rose; another caught on the edge. The polyps caught food while helpers topped up the cooling system. Outside, the current flowed on. Inside, everything needed careful tending so that the family received enough fresh seawater.

People tried to give threatened colonies a small sheltered space of water. The shimmering capsule was one of these inventions. Outside, substances from the inhabited world kept passing by; inside, the exchange with the dark sea had to remain open. A shimmering shelter surrounded the next relative. Small bubbles gathered around the upper edge. Inside, red, green and yellow branches gleamed. Fresh seawater entered through a narrow inlet. The family stayed connected to the sea within it. A polyp caught its meal, and outside the great current flowed on, too large to fit entirely into the little space.

People had damaged the open reef and wanted to care for individual colonies inside coverings. Little propellers moved the water within them. People had to keep checking whether enough food and oxygen arrived; a wall could not do that by itself. Around a blue relative, little propellers were attached to a covering. They spun and kept the water moving inside. The polyps stretched their feeding arms into it. Outside, a fish passed. Only a thin wall lay between its open sea and the sheltered branches. Even so, these were very different places for their residents.

Warmer water and fewer supplies from cool currents made some deep places difficult to live in. People kept sheltered spaces of water open around individual colonies. The green shapes outside were part of their invented covering, not a seagrass meadow. A transparent covering surrounded the red relative. Outside, green threads moved and tiny bubbles rose past. Inside, people made sure fresh seawater kept arriving. The covering could not shut everything out. ‘We still need a little bit of sea,’ whispered a polyp, stretching its tentacles into the small current flowing through the sheltered space.

People still kept individual shelters running and removed particles from their coverings. Outside, the sea remained full of widely scattered traces. The longer the supplies continued, the clearer it became how much these places depended on regular help. A red bubble surrounded a blue-green relative. Outside, colourful particles gathered at the edge; inside, there was more space between the crowns. Red threads held the covering in shape. A helper carefully brushed the outside clear and took the dirt away. The polyps waited in the sheltered water. Afterwards, even the smallest of them could stretch out their tentacles again.

People supplied small spaces of cleaned water on the deep seabed. Pipes, mats and collecting arms needed power and maintenance. Because the rubbish from the world above did not stop, the helpers had to return before new loads clogged the protective system. The green relative stood in a bubbling shelter. A purple filter mat hung on the left, with pipes and small devices leading into the water beside it. An orange arm collected larger pieces. The helpers often returned to empty everything and bring in fresh seawater. The family now lived in the middle of a small installation, whose quiet work accompanied every one of their days.

Outside the covering, the water kept changing because of human emissions and interference. So people maintained a small shelter. Fresh seawater and food had to get in, or the protection would have become a dangerous seal. A transparent covering surrounded an orange-yellow colony. Its pink polyps opened inside while the sea flowed past outside. A little fish swam around it and found no way between the branches. The colony was protected. But it still needed food and fresh seawater. A covering alone could give it neither.

People still brought supplies and tools to the last shelters under their care. They checked pipes and controls. By now, many hiding places and routes for food were missing from the rest of the sea; no single device could replace the whole ruined neighbourhood. A clear covering surrounded the next relative. At the top, a pipe brought in water carrying food; at the bottom, a control showed the temperature. Blue lines marked the electrically protected edge. The helpers checked the installation regularly. Inside, pale and dark crowns opened in the little circulating flow. The family was well supplied as long as someone remembered to come back the next day. But after this visit, no human ever returned to this reef. It had been the last one. The family could not know what was happening elsewhere in the world.

After the last visit, no one came to the reef for a long time. The built installations received no more supplies. Later, they fell apart or other animals settled on them. The sea kept changing too; life returned in some places. The few scattered branches of this family had to make do with what they now found. Where people had once damaged reef slopes, there were now different neighbourhoods. For this family, the places they could live remained far apart. Their living neighbours were still there; the help from equipment had long gone. Many little bubble chambers nestled around the branches of a pale relative. Each curve followed the next, until the whole colony wore a second outline. Fresh seawater reached the polyps between the chambers. The family kept its protection close. But outside, the sea still flowed, and the next tiny meal would also have to find its way from there.

No human ever returned to this reef. Some damaged slopes were inhabited again by now, but this family had found no new beginning there. In the few places they had left, there was barely enough food for everyone. Small living helpers worked together on a pale relative. Fine pathways linked the branches, purple glands kept visitors at a distance, and below, a living mesh caught particles. Tiny cleaners loosened some of them again. But more and more stayed caught. The family had developed plenty of protection; even so, their lives depended on the current bringing enough food for everyone.

No human had come to this reef for a very long time. Much had changed in the sea, yet large empty stretches still lay between the last colonies. Their larvae found no new home there. Even further out lived a heavily protected branch of the family. Small living cleaners brushed its branches; the invented light crystals glowed between them. Armour surrounded the delicate tissue. When a cloud of particles came, the polyps closed. Afterwards, the cleaners began working again. But they all needed food, and the current brought less and less. Far apart, the last colonies waited.

Many, many generations had passed. People had long since stopped coming to this reef. Some of their structures had fallen apart, and animals were living again in other places. But the lost reef slopes had never become a home for this family again. Its last colonies stood far apart. Towards the end, the family had lived in only a few sheltered places. But even there, the current had to bring enough food. For a long time, too little arrived. The last polyps closed. They did not open again. No member of this family was alive anywhere else either. There was no larva and no living polyp from which it could grow again. The coral family was extinct. Its pale calcium carbonate branches stood in the water for a long time. Then, little by little, they broke. Over many more years, the water carried pieces away, and sand covered the remains. When the current returned, it flowed over the empty seabed. ‘Who lives here?’ This time, nobody answered. The coral had once stood here.

Fictional year 2,002,026 · 90,026 years after the last visit
The coral family is extinct.