Edited by Timothy Donald Morris.

In the memory of mankind, Greenland has remained a harsh ice-covered island almost all the time. However, its name means simply “green land” – that’s how the first European settlers, who came to this land during the warming period, called this island. But after that, nature took its course, and for many years the island was covered with ice. During the ice age at the turn of Holocene and Neocene, Greenland was buried under a kilometer-thick ice, and life on this island was completely impossible.
In the Neocene epoch, the climate has changed in a favorable direction. The Atlantic has become much wider than in the Holocene, and the Gulf Stream has deviated from the shores of Europe, and now washes the eastern shore of this island. But winter has not completely given up: part of the island is located beyond the Arctic circle, and here the polar night is replaced by the polar day. Therefore, Greenland has become a kind of refuge for relic species that lived on the Earth during the Ice Age.
The flora of the island has become much richer than it was before. In the south of the island, taiga grows with patches of small-leaved tree species (birch and aspen) along the rivers. The north is occupied by thickets of deciduous and low evergreen shrubs, which in winter are completely covered with a thick layer of snow. There are many sphagnum swamps, and lakes with clear cold water exist in the river valleys.
In the nature of Greenland, the seasonal changes are clearly expressed. And, even despite the warm climate of the Neocene epoch in general, winters are snowy and quite cold here.
Beyond the Arctic Circle, winter and the polar night mean the same things. For several months, there is almost complete darkness here. Only the aurora silently flickers with pinkish and greenish lights over the snow-covered plain. It seems that all living things either fell asleep, or hid under the snow, or froze to death. However, this plain is inhabited, and creatures much larger than mice live here.
The snow creaks under the paws of a large beast. Leaving a wide track in the snowdrifts laid out a few hours ago, a huge snow porcupine, covered with warm white winter fur, wanders across the plain. It is heading south, toward the woods. The snow layer on the plains became too thick lately, and it is increasingly difficult to dig it up in search of plants. The fat stocks that this beast has accumulated over the autumn have already been depleted. If this weather lasts for another couple of weeks, the huge beast may not live until spring.
Its hopes for survival are connected with the southern forests. Trees grow in the southern parts of the island, and the snow is not so thick here. On the plains, the tops of shrubs and stunted trees stick out from under the snow only in some places. They have already been gnawed: other snow porcupines have visited this place before. Having sniffed what its relatives left after their feeding, the snow porcupine begins to dig up the snow with its front paws. After half an hour of hard work, having dug a huge hole, the beast can expect to a meager lunch: yellow stalks of last year’s grass appear from under the snow. The snow porcupine bites them almost to the ground level with its huge incisors. Of course, for a large beast, a few tufts of grass are not enough to be sated, but it is enough to numb the pain in the stomach. In addition to grass, the porcupine bites off twigs of a shrub. In times of famine, such food will do quite well.
The huge rodent travels across the plains of Greenland not alone: two large marsupials – geopossums – are running following it. They have short legs, and they get stuck in deep loose snow. But it is much easier for them to move along the trail of the snow porcupine. Geopossums do not eat grass, and they are not interested in what the snow porcupine eats. These animals are carnivorous, but they cannot attack a snow porcupine: with a blow of its clawed paw, this rodent could throw the largest geopossum a few meters away, or squash it flat. The favorite food of these animals is small animals, and the porcupine, digging up snow, scares them away, and geopossums may also be lucky.
As the snow porcupine moves south, it eats better and better: it finds shrubs and sometimes young trees often. Occasionally it sees its congeners who also migrate from the north. This rodent species is not in the habit of getting too close to its congeners, and it declares its presence by “renewing” the piles of droppings left by them. By the smell of the droppings, any of its congeners will receive the necessary information about its presence in this territory.
But if for its congeners this snow porcupine is just one of the representatives of their species, then for other inhabitants of Greenland it can be like a natural disaster. The snow porcupine finds a place where the snow is quite loose. It feels the bushes covered with snow, and begins to dig them out in the hope of refreshment. It does not notice one feature that distinguishes this place from the surrounding landscape, but the accompanying geopossums quite rightly expect for a good meal. All the snow is riddled with holes: a snow porcupine accidentally came across a settlement of small rodents, Greenland chipmunks. These rodents arrange large settlements in the bushes – “towns” numbering up to a hundred nests woven between branches and lined with dry grass from the inside. In winter, when the snow covers the bushes completely, Greenland chipmunks dig a lot of holes in the snowdrifts, along which they can run without being noticeable from the surface of the snow. Digging up snow layer in search of food, the snow porcupine destroys the holes of chipmunks. The small mammals disturbed by it whistle drawlingly, notifying each other of the danger, and thereby give away their location to predators. Geopossums are solitary predators, but hunger makes them forget about the need to keep a distance, and they almost simultaneously rush at small mammals that run out from under the paws of a heavily snuffling giant. It is very difficult to hunt small agile prey in the polar night, but a keen sense of smell helps geopossums. Both predators were lucky: each of them caught an animal.
Having got the prey, geopossums begin to keep their distance again: unfriendly squinting at each other and baring their teeth, marsupial predators disperse to the sides and eat the dead bodies of chipmunks.
Geopossums usually follow snow porcupines during the winter, or move to places where the snow cover is not so thick. It is difficult for a short-legged predator to search for food on plains swept by snow, so geopossums relentlessly follow their spiny patron. However, this time one geopossum leaves the snow porcupine of its own free will. This is a female, and she feels that a very important moment in her annual cycle is approaching: she is preparing to bear offspring.
The female geopossum takes one last look at the retreating snow porcupine, followed by her congener mincing. She goes to where the branches of a low-growing willow tree stick out from under the snow, and a large snowdrift is formed near them. The geopossum female begins to dig in the snow, and soon completely hides in it. When a blizzard begins, the hole in the snow quickly covers with drifts, and the female appears covered from all sides. Tossing and trampling the snow with her paws, she expands her shelter, at the same time making the walls more dense and impervious to wind. From her breathing, the temperature in the snow hole rises, and the female falls asleep for a short time.
A few hours later, the female woke up: her labor pains began. Turning on her back and curled into a ball, she gives birth to several underdeveloped worm-like cubs. Her breath warms them, and small living lumps hurry to take their places in a warm cozy brooding pouch.
Another hour passes. The female geopossum begins to dig snow, and soon leaves her temporary shelter, carrying four of the luckiest offspring in her pouch. They will have a very big chance to live at least to the age of three years. Maybe some of them will live a full life, reaching its old age. And at the bottom of a snow hole dug by the geopossum female, in the cold snow, the bodies of five more cubs lie, motionless and blue from the cold. In the cold, they died in a few minutes, but their tiny bodies did not lie in the snow for long. The wall of the geopossum’s burrow moves in one place, several lumps of snow fall out of it, and the muzzle of the Greenland chipmunk appears from the hole. Apparently, during the attack of some predator, it failed to find its way to the colony. The rodent is severely emaciated: he has not eaten for the last two days. After sniffing, the chipmunk rushed into the middle of the hole and began gnawing greedily the frozen cubs of its worst enemy. The geopossum cubs died, but due to their frozen bodies, this chipmunk will survive and be able to find its way back to the colony.
At the end of winter, the sun begins to return gradually to this frozen region. The first day lasts only some minutes, and the upper edge of the Sun disk is only slightly visible above the sea. But every day the sun as if grows bolder. Time passes, and the sun is already fully rising above the horizon.
A warm wind is blowing more and more often from the ocean. The top layer of snow melts during the day, but freezes again at night, forming a strong crust on the snowdrifts. The layer of the crust is so strong that the geopossum can walk and run on it without falling through. Of course, this facilitates the movement of the beast, but significantly complicates its search for food. It is difficult to break through the ice crust, and the snow porcupine, followed earlier by the geopossum female, which now has cubs, has gone to an unknown destination. Therefore, the female geopossum herself is forced to move to where it is easier to search for food: to the seashore.
It is noticeably warmer on the Atlantic coast than in the inland areas of the island. Here, the snow has already begun to melt a little, and the seashore is completely free of snow cover. It is warmer here than on the plains, but it is very damp also. The wind carries fine water spray from the ocean, and the coat of the geopossum female gets wet soon, despite the fact that the beast shakes it often. But this is only a small difficulty.
There is a lot of food at the seashore, especially after a storm. Here it is possible to find dead fish and decomposing carcasses of sea monsters unfamiliar to the geopossum female. It is unlikely that she will want to know what they are called and who they are. She needs food more than anything in the world, and so the stocky beast minces along the surf line, sniffing everything that the sea has cast ashore. Usually these are branches of trees, sometimes even those that grow in the far warm southern lands. But amidst the smell of wet rotten wood and the pungent stench of seaweed, the sensitive nose of the beast caught the smell of something obviously edible. The geopossum female followed the direction of this attractive fragrance, and soon hit upon something that looked like a tree trunk at first glance. Upon closer examination, it turned out to be the carcass of a large shark, about 4 meters long. The jaws of the predator are forever bared in a sinister grin, but they will not harm anyone anymore. There are several scars on the body of the fish – it clearly got into a fight with its congeners and lost. Shark meat is frozen, but it can be chewed – geopossums have strong jaws. The female eats meat with pleasure and feels a surge of strength and a pleasant feeling of satiety. Now she is not afraid of the cold and the cubs in her pouch will grow normally. She will stay near the carcass for several days, gradually gnawing on the dead shark.
On the plains, life goes on as usual. The sun lingers longer in the sky, and it gets warmer every day. Feeling the approach of spring, herbivorous mammals leave the forests and shrubs of the southern part of the island, and return to the north. Large snow porcupines walk alone, but other inhabitants of the northern plains move north in large herds. These animals are representatives of the few ungulates in the Neocene. From a distance, they look like large elks, but if you look closely, you can see their main difference from the elk or reindeer of the Holocene epoch. Each of these animals has only one large antler on its head, which forms a kind of “shovel” in front part, allowing the beast to dig snow. The back of the horn is directed obliquely, and because of it these animals are called skewhorns. Skrewhorns are the descendants of reindeer; they have preserved many features of the behavior of these animals.
A herd of northern skewhorns feeds on the plain. These beasts dig up the snow with lateral movements of their heads, working with the “shovel” of the hypertrophied antler. Under the snow, they find food – grass and leaves of evergreen shrubs. A lone geopossum watches a herd of skewhorns. He made do with random food for many days, while there was a layer of crust on the surface of the snow. Massive ungulates, crushing the crust with their feet and blows of their antlers – it looks like an invitation to dinner for a small predator. The geopossum male dared to act: he leaves his shelter, and walks quite openly to the herd of skewhorns. He would not be able to attack such a large beast; he is more attracted to the digging places that the skewhorns leave. Having felt the approach of the geopossum, skewhorns stop digging snow. The beasts are on alert: they mumble jerkily, shake their heads and step aside when a stocky predator approaches them. But the geopossum does not pay attention to the giants: he begins to rummage in last year’s grass, searching for insects that hide in it. Gradually, the skewhorns begin to get used to the presence of the geopossum, and only snort and shift from one foot to another when the geopossum male comes too close to them. While calves have not appeared in the herd, adult animals are quite tolerant of its presence. It seems that the geopossum will spend the rest of the winter well: it begins to accompany a herd of these ungulates.

Picture by Sauron

Spring in Greenland comes earlier than in Europe at the same latitude due to the fact that the Gulf Stream now heats the coast of this island. The wind carries clouds from the sea; after the rain, the snow becomes loose and porous, the snowdrifts thaw quickly and thaw holes appear between them. Ice breaks on the rivers, and they overflow their banks. At this time, those who survived the winter in hibernation appear on the ground surface.
Between the drifts of thawed and grayish snow, a long-bodied creature, similar to a lizard with bare, slimy red skin and short paws, makes its way. It is the serpentina, a large local amphibian species. Meltwater flooded the burrow where it spent the winter, and now the awakened animal is crawling to the river. The sun has warmed the topsoil, and serpentina decides to rest a little. It lies down on the warmed ground and absorbs with its whole skin the warmth of the sun, poor for now. It has no one to be afraid of: there are many poisonous glands on the serpentina’s skin, and any predator will have a bad time if it wants to taste this amphibian.
After warming up, the serpentina continues on its way to the river. It finds a stream, enters the water and swims, having pressed its paws against sides and wriggling gracefully its whole body. The river has overflowed, and many streams flow into it, along which other serpentinas haste into the main channel of the river from forests and shrubs. After they have lived in the water for a while, the mating games begin. The coloration of serpentinas changes in a few days from normal one to courtship dress. Males turn intensely orange with large black spots merging into a mesh pattern on the upper half of the body. On the skin of females, black spots disappear, and they turn pale. Males engage in duels with each other for the areas near the shore where the current is not so strong. When a female ready to reproduce swims past such a gallant, the male begins to invite her to his site: he wraps around her body, pushes her by head towards his site, and holds her by paws against the base of the tail. If the female accepts his courtship, the male lays spermatophores on a stone or a flooded tree trunk, and the female picks it up with her cloaca. These amphibians have internal fertilization, and they are viviparous. In summer, the females will produce two large juveniles ready for independent life.
The snow porcupine sheds the coat in spring. The large rodent scratches against trees, leaving patches of thick winter fur on them. Old spikes also stick into the bark, but it is not a problem: they will grow back soon. The porcupine travels alone: the geopossums left it when the first thaw appeared in the snow. After scratching itself thoroughly, the porcupine shakes intensively in a dog manner, and shreds of wool scatter from it in all sides, as well as a considerable amount of spikes.
Small songbirds have migrated to Greenland from the mainland, and are now busy building nests. They quickly pull apart the porcupine’s wool to line their nests.
There is still little food on the shore: the grass has not grown to the right height, and the tree bark is not the best spring treat, although it is useful: porcupines heal themselves of helminths with the help of bark. But some kinds of food may still be found at the seashore.
At the rocky seashore, as soon as the water warmed up enough, the rapid growth of macroalgae began. It is difficult to go down to the sea, but there are several places on the shore where it is convenient to do this. Many generations of snow porcupines went down to the sea for seaweed, or just to drink salt water, and in some places, the cliffs collapsed, forming a convenient descent to the sea waves. The giant rodent, carefully stepping with its paws, descends along the rocky shore. Some of its congeners did not succeed: aside from this descent lies the skeleton of a snow porcupine: last year a stone slipped from under the paws of this giant, and the animal fell from a fifteen-meter height, breaking its neck. By that time things came right, and the giant rodent comes out to feed on the coast, being unharmed. It greedily eats strands of seaweed cast ashore. It is not only delicious, but also useful: they are rich in various microelements, which has a beneficial effect on the health of the animal weakened by winter lack of food. The snow porcupine becomes more and more picky, as it gets satiated: it no longer chews all the algae, but rummages through piles of plants cast ashore by waves, choosing fresher and tastier ones. It has new companions – northern crails, long-legged, crane-looking birds. A couple of these birds have just returned from wintering grounds, and now they want to feed up after a long flight. The snow porcupine interested them in its activity: from the algae that it is stirring, from time to time the crabs that basked in them run out. This is what crails need: birds catch crabs disturbed by the beast, catching up with them and killing them with well-aimed pecks of their beaks. For a while they accompany the snow porcupine, just as geopossums did in winter. But, having had enough, the birds run along the shore, flap their wings and take off. After making a few circles in air over the giant wandering along the shore, they fly away to the north.
The snow porcupine also does not intend to stay on the seashore for a long time. These rodents will soon begin the mating season, and it must hurry to the plain not to miss an opportunity to have offspring. Unlike many rodents, snow porcupine gives birth to one cub, and does it once every two years. Accordingly, not every female is ready to accept the courtship of males.
The snow porcupine male sniffs the piles of droppings left by its congeners. And soon it catches the scent desired by any male at this time: the scent of a female. The male remembers it, and begins to look for its source. The dung is quite fresh, and the search does not last long: among the low-growing willows near the stream, the male sees the object of his lust. An adult snow porcupine female, standing on her hind legs, bends the willow tree towards her, and nibbles off young branches with young unfolding leaves. When the male approaches, the female looks at him blankly, and then continues to eat. The male takes some more steps and begins to purr invitingly. But this action does not impress the female. She is pregnant, and therefore is not ready to accept the male’s courtship. When the male comes even closer to her, she bristles and turns her head to him. After his another careless step, the female bares her incisors, clearly showing the intention to fight. She will give birth soon, and will take care of her cub for a long time. Therefore, she is indifferent to signs of attention from males.
In the spring, all living beings feel that a huge burden of worries related to the struggle for life has fallen from them. And some animals feel it literally. In the spring, the skewhorns shed their huge antlers, which faithfully served them throughout the winter. Sensing that the antler will shed soon, the animal more and more often scratches its head against tree trunks or digs the ground with its antler. And one day the antler sheds with a slight crack. The “bald” skewhorn shakes its head in relief, sniffs at what used to decorate its head, and leaves. What fell is gone. But it is true not for everyone: some inhabitants of Greenland perceive the fallen giant’s antler as a very useful thing for them. Greenland chipmunks find a shed antler of a skewhorn, and gnaw it, just as mice gnawed shed elk antlers in the Holocene epoch. Rodents replenish the reserves of calcium and other minerals in their bodies: they will soon have offspring.
Having freed themselves from the antlers that burdened their heads, skewhorns rest and feed on young shoots of shrubs. The herd is in no hurry to leave, and stays in one place for several days. The animals are preparing for a very important event in the life of the herd: skewhorn female will soon start calving. Females form groups where all animals are approximately equal in position in the hierarchy. So they experience less stress, do not suppress each other, and do not engage in squabbles. When all animals are calm, it is easier for them to synchronize their biorhythms: the females, ready for calving, secrete in their sweat a substance from the smell of which the development of the fetus in other females is slightly accelerated. Finally, one by one, the females bring offspring. The skewhorn cubs are born very well developed. In the first minutes after birth, they try to get on their feet, and quickly learn to walk and run. The mother licks her calf, and it remembers her smell, which it will not forget as long as it depends on her. For the first hours, the female drives away even her own relatives from the calf. All skewhorn deliver within a few days.
After the birth of the cubs, the skewhorns become more aggressive: in every small animal they see a danger to their offspring, and often quite rightly. Small predators of Greenland, like geopossums, can steal a skewhorn calf on occasion. And one such hunter lurked in the bushes near the clearing where the skewhorn females give birth. This is a geopossum female with small cubs on her back, and she is hungry: the cubs require a lot of milk, and in recent days she has rarely been able to eat well. The geopossum female has been watching the skewhorns for a long time, and after waiting for the moment when one of the females completes fawning, she tries to attack the newborn calf. But the attack is unsuccessful: she is driven away by a female who has already given birth, which stays nearby. A large animal stomps its hooves threateningly, and the geopossum retreats into the bushes. When the skewhorn calf tried to get to its feet, its mother drove off her relatives, and the geopossum female had got another chance. She rushes out of her hiding place, and attacks again. But the young skewhorn female managed to push her calf aside, and her wide hoof stomped on the grass right in front of the geopossum female’s head. However, the geopossum female manages to steal and eat her afterbirth.
Some more days later, all the skewhorn females gave birth, and the animals move away. The geopossum female visits their “maternity hospital” again: she knows from experience that there is something to profit from here. She finds the corpse of a stillborn skewhorn calf and eats it with pleasure, gnawing its soft gristles.
The noise of the wings above her head makes the marsupial predator distract from food, and a three-meter-wide shadow glides along the ground. An adult northern crail lands next to a feasting geopossum female. These birds feed on small animals, and do not miss the opportunity to eat carrion. In spring, in high water, crails roam the flooded plains, hunting rodents in distress. The geopossum female has a good idea of how such a meeting can end, and she turns into an attack: she opens her mouth and begins to make a dab at the long-legged bird, growling loudly. The crail, clearly not expecting such ferocity from a smaller animal, runs away and waits until the menacingly purring geopossum female is sated. When the geopossum steps away from the half-eaten carcass, the bird grabs the remains of the skewhorn calf and drags it aside. After making sure that the geopossum is gone, the crail begins to tear off the shreds of the skin greedily and peck off the crumbs of meat from the bones.
Geopossum cubs grow up, and in late spring they become quite independent. They are already filled with curiosity, and move away from their mother, exploring the world together. But this research can provide experience at too high a price. Young geopossums find a strange object: a pile of twigs and grass stacked on the ground among tall grass. They come closer, and then one by one they climb to the top of this pile. There, one of the geopossums discovers a neat depression lined with grass, where two large eggs lie. Without knowing it, the young geopossums wandered into a place dangerous for them – the nest of the northern crail. When these geopossums were still sitting on their mother’s back, they had to see her ravage the nests of small birds. And here it is an incredible luck: they found a nest with large and very tasty eggs on their own! One of the geopossums is trying to steal a crail’s egg. It crawls under egg with its muzzle and rests its hind legs, trying to push the egg out of the nest. It almost succeeds, but for the completion of this plan, the animal lacked some few seconds. A huge bird appeared on the nest – the crail female returned from feeding, and caught the thieves by surprise. A huge bird frightened the geopossum cubs, and they scattered and disappeared into the grass. Only the bravest of the young egg thieves did not have time to escape: getting out of the nest, it pinched its paw among the twigs, hesitated for a second, and the beak of an angry crail female killed it on the spot, piercing through the skull of the animal and literally pinning it to the ground.
After making sure that nothing threatens the nest, the crail female put the egg right and removed the carcass of a young geopossum from its nest. Having thrown it to the ground, the bird pressed the carcass with its foot and began to peck. Piece by piece, the body of the geopossum disappears into the bird’s throat. After finishing lunch, the crail female rose to the nest and continued brooding her eggs. Gradually, she warms up in the sun and falls asleep.
In the spring, the crails molt – the winter plumage is pretty frayed and needs to be renewed. Birds molt very quickly: when the bird shakes, fluff and feathers just fly in all directions. And literally right there young feathers, twisted like thorns, stick.
The wind stirs the crail feathers scattered around the nest. They will not be wasted: small animals hunt for them, despite the fact that an adult crail, if possible, will eat any of them with pleasure. The back of a Greenland chipmunk flashes among the grass – the rodent gathers feathers, and lush black-and-white “whiskers” already stick out on the sides of its mouth. This is a female, and she warms her nest – she has cubs. But it will not be possible to gather the feathers calmly: there are too many ones who want to take away this precious burden. One of her congeners runs to the lucky collector with the obvious intention of taking away some of the found feathers. At first, chipmunks chase each other, then the alien one pulls out some gathered fluff from the thrifty female’s mouth. The offended female rushes after the robber, both animals tear out feathers from each other, fight and roll on the ground with a squeak. From their noise, the crail female wakes up and jumps to her feet. Immediately, an alarming whistle of one of the animals is heard, and the living tangle breaks up: both chipmunks run away, and the wind blows the feathers that caused this brawl.
Not only small animals are afraid of crails when these birds hatch eggs. When the female is sitting on the nest, she is almost invisible because of the dense grass, which seems to be in a hurry to catch up for the winter. A skewhorn with shed antler stolidly wanders across the plain and passes very close to the crail’s nest. Suddenly, almost at point-blank range, a tall bird “grows” out of the ground. The skewhorn jerked to the side in surprise, and, as if sensing its fear, the crail female begins to drive the beast away: she opens her wings wide (in which many feathers are clearly missing) and rushes on the beast that exceeds her weight many times. The bird bravely pecks the skewhorn in the muzzle several times, and the ungulate retreats. The skewhorn shies away from the crail’s nest, cautiously squinting at the bird, which menacingly clicks its beak and opens its wings wide.
A real polar summer is coming. The sun is almost constantly in the sky: it only “strikes” the horizon in the north with the lower edge of the disk, and then stops setting at all. There is an excellent warm weather. Occasionally rains come from the Atlantic, and this contributes to the growth of grass and trees. The branches frozen over the winter and bitten by herbivorous animals are restored, and the trees even have time to add considerably in growth. At this time there is an important event in the life of snow porcupines: the females give birth to cubs. Snow porcupines are descendants of South American rodents, and they are characterized by the birth of only one or two cubs. Greenland chipmunks, which scurry among the bushes looking for food, have up to five or six cubs at once, but they are born naked and blind, and for the first two weeks they constantly keep in a spherical nest woven from branches. But the cub of snow porcupine is already covered with fur at birth, its eyes are open, and a few minutes after birth it tries to stand on its feet. The baby is still completely defenseless: its teeth have not erupted, and there are no spikes in its fur at all. The female jealously protects her cub from possible danger.
The geopossum in the Neocene-era Greenland ecosystem occupies the place of a fox and a hyena simultaneously. It hunts small prey, eats carrion, and sometimes tries to attack the cubs of large animals. The baby of the snow porcupine did not have time to get to its feet for the first time after birth, and it is already an object of predator’s attention: the geopossum is hiding in the bushes, waiting for a convenient moment to attack. But the mother of a newborn porcupine already has a painful experience: many years ago she lost her firstborn immediately after its birth, when she lost her vigilance. Therefore, she is on the alert, and the careless movement of the geopossum almost cost it its life: the snow porcupine female rushed at the predator, and a huge claw plowed deep into the turf literally by a hair’s breadth from the predator’s head. The geopossum saw fit to retreat as quickly as possible.
Parental lessons are very important for the survival of offspring in the future. The more attentive a young student is, the more chances it has to live to old age. Young crails, like the snow porcupine cubs, are able to stand firmly on their feet after about half an hour after entering the world. By summer they have grown up and wander with their parents across the plains and shrub thickets. In such places, they can find enough food: insects, frogs, and even something more substantial.
The shrubs are occupied by a colony of Greenland chipmunks. These animals settle in “towns” and build many nests in the thick of bushes, clearly preferring the thickets of prickly Greenland raspberry. The nests are woven from twigs and grass, and it is sometimes very difficult to approach them. But this is not a problem for crails: they have small heads, and their strong beaks are insensitive to pricks of thorns, which cover raspberry branches. The family of crails wandered near the Greenland raspberry thickets when one of the chipmunks raised the alarm with its loud whistle. This could have saved the animals from large predators that would not fit into the thick of prickly stems, but for the crails, the whistle of the sentry sounded like an invitation to dinner. The crail family approached the bushes, and began to ravage the nests of Greenland chipmunks. The powerful beaks of birds easily tear the nests and shake out their contents. Sometimes the crails got the rests of last year’s food – wormy dry mushrooms or berries, but in several nests the birds found what they were looking for: broods of young chipmunks. For birds, this is a tasty food, and the baby chipmunks, without even having time to squeak, disappear into the beaks of the crails. Such an event may seem like a tragedy at any given time, but in general, such events are set forth by nature and do not affect the number of chipmunks. The nests will be repaired or made anew, and another brood of chipmunks will be grown in them over the current summer.
In summer, all the animals of Greenland have one common enemy, the insects. Swarms of annoying midges swirl over the swamps, and on the plains they are replaced by loud buzzing annoying horseflies. These insects literally get stuffed into the eyes and ears of large mammals, inflicting painful stings on them and driving the animals almost to frenzy.
Young crails, in whose wings the flight feathers have already start growing, initially perceive the attacks of horseflies as a game: they chase large flies themselves, knocking them down with their beaks hitting the insects accurately. However, when the chicks get tired, the horseflies pass to attack and the young crails have to hide in the bushes to escape from them.
Huge snow porcupines are covered with pointed spikes, and are able to repel even large predators. But they suffer from the stings of the tiniest and most fragile creatures inhabiting Greenland – midges. The porcupine female has watery eyes from midge stings, and her cub constantly scratches its muzzle with its paw: its skin itches unbearably. And two porcupines go into the woods, away from the wetlands. Insects chase them for a while, but in the forest the swarm of midges is noticeably thinning: small birds fly around porcupines and catch these bloodsuckers. Finally, the animals can rest a little and eat in peace. The porcupine mother rises on her hind legs and bends the branches of low-growing trees towards her. With her powerful incisors, she strips the foliage from them, and slowly chews it. There is no need to shake her head and wave away the insects, which seem to only rage from this. But the stung muzzles of the female and her cub hurt, and the snow porcupines move to the river. Here the little porcupine gets one of the valuable lessons of survival: it learns what thing helps from insect bites. Its mother lies down in the mud on the gentle river bank, and wallows in it with great pleasure, shaking herself from time to time. Imitating its mother, the porcupine cub dips into the cool mud, and heaps it on its muzzle. The burning sensation from insect stings subsides, and both animals enjoy peace.
When the porcupine female and her cub get out of a mud bath, the mud dries on their wool and forms a kind of shell that saves them from insects. Protected by dirt from midge stings, huge rodents dig up the roots of reeds at the shore and graze calmly, from time to time wiping the dirt flowing from the wool over their eyes with their paws. This, of course, causes inconvenience, but for the sake of a few hours of a quiet meal, they can be patient.
The river waters are full of life. Nymphs of various insects feed on plants or hunt each other, and they are all hunted by long-bodied creatures that swim in the water, serpentine bending their bodies. They have brown bodies with bright yellow bellies, and three pairs of short “feathers” stick out on the sides of the flat head in them. These creatures are serpentina larvae. They are not too similar to their parents yet, and besides, they are not poisonous yet. When a pair of snow porcupines passes along the shore, young serpentinas rapidly bury themselves in the sand, leaving only the head with gills outside. The adult serpentina is not as timid as its offspring. Sparkling with bright colors, it does not hide even at the sight of huge snow porcupines. It doesn’t care about them as long as the beasts are passing by, and it calmly rummages in a moss cushion, searching for insects. The snow porcupine cub is very curious: while its mother is busy eating, it pays attention to the serpentina, as if it were a bright toy. The cub comes up to it, first sniffs, and then tries to push the bright creature with its paw. Its behavior instantly causes a protective reaction in serpentina: the amphibian begins to wriggle in figure eight and displays its bright belly. An unpleasant smell spreads from it, and the porcupine cub steps aside, deciding not to mess with such a bad-smelling creature anymore. The female is distracted by their noise, notices a bright creature writhing in the grass, and calls the cub to her. Having slightly bitten its scruff of the neck, she leads it away from the poisonous creature.
In summer, the antlers of skewhorns begin to grow again. Every animal, having survived another winter in its life and having retained enough vitality, receives a “promotion in rank” from nature: every year it grows an ever larger antler. Only the antlers of old animals become smaller with age than in the heyday of their strength. The forming of a huge antler requires a large amount of mineral substances, so the animals move in whole herds to the river, where limestone layers appear at the ground surface. The territories where this rock is present are divided between herds, and only a few lonely ones can enter the occupied territory while the rightful owners of it are feeding somewhere else. When the herd comes for feeding, the animals begin to look for a place where the rains have exposed fresh limestone outcrops. Skewhorns dig the ground with their hooves, pick and bite off clay, and even gnaw pieces of weathered limestone. This behavior, of course, causes them some digestive disorders, but helps to build a huge antler that is very helpful in the harsh winter time.
A herd of skewhorns wanders across a slightly swampy plain to one of the rivers, waving insects away. They return from the seashore, where they went to drink salt water and feed on algae. Wide hooves help the animals not to get bogged down in wet soil. But nature sets traps in the most unexpected places. Gullies and pits filled with water have formed under the soil since spring. The plants formed a carpet over the trap, intertwining their roots into a relatively dense sod. An adult geopossum can easily run across it, but massive ungulates or snow porcupines cannot pass through here. A skewhorn male, which, judging by the size of its antler, may become the king of the herd this fall, accidentally got into such a trap and sunk in a quagmire. When the ground trembled menacingly under the hooves of the skewhorn male, he made a mistake: he rushed sharply to the side, and one of his hind legs broke through the sod and sank deep into the mud. If he hadn’t made any sudden movements, he might have been able to get out thanks to his wide hooves. But he makes one mistake after another: in fright, he kicks the carpet of plants too sharply with his hooves, and another foot falls into the liquid mud. The frightened male bellows loudly, and the herd rushes away in fear, leaving him alone with his own problems. The massive antler, even if not yet fully grown, has turned from an advantage into a hindrance – the beast cannot get out of the quagmire. The carpet of plants does not withstand the attempts of the skewhorn to free itself, and the beautiful mature male drowns. In many swamps there are skeletons of such large-horned males. Like Irish deer in the past, skewhorn males often die in swamps, especially closer to autumn, when their heavy antlers are fully grown. However, this is only one side effect of sexual selection. In the autumn, during the rutting season, the benefit of a huge antler covers the mortality of animals from such accidental causes. Then the surviving horned male has a chance to leave numerous offspring that will inherit paternal qualities.
Summer is a time of abundance. At this time, every living being can choose food to taste, and eat their fill. Young geopossums have already become completely independent, but they still stick together. They catch all kinds of aquatic life in the river, searching between the stones with their fingers. The dragonfly nymph or snail is immediately shoved into the mouth before it is taken away by their own siblings. One of the young geopossums is pawing in a particularly deep hole, and suddenly jumps out of the water with a squeal. It’s hard to say who caught whom: the geopossum groped with its fingers for a large crayfish, and it immediately clung to the predator’s paw with its claws. The geopossum squeals loudly, trying to shake off such a belligerent prey from its paw. And at the same time, it does not want to share prey with its siblings who gathered around the lucky hunter. One of its brothers, seizing the moment, tears the crayfish from its paw, crushes it with a bite and begins to eat. It is unlikely that it will manage to eat more than a quarter of this prey – its siblings, led by the victim of the crayfish’s claws, pounce on the thief, and a fight ensues on the riverbank. It ends with one of the young geopossums grabbing the crayfish and dragging it into the bushes before the others realized that the subject of the conflict had disappeared.
Summer is gradually coming to an end. The sun stays below the horizon longer and longer, and the nights are getting longer and colder. Yellow leaves appear on the trees, and every day there are more and more of them. Autumn offers the inhabitants of Greenland mushrooms and ripe berries. Skewhorns and snow porcupines are eagerly searching for them. But the most active consumers of mushrooms are Greenland chipmunks. These thrifty rodents, like squirrels in the Holocene epoch, prepare supplies for the winter. Berries (especially cranberries, rowan and arrowwood, which can be stored for a long time) are put by animals in non-housing nests, carefully plugging the entrance with a bunch of grass. The walls of the nest are slightly blown through by the wind, and the berries are stored in it until the middle of winter. These rodents prick mushrooms on thorns or shove them into the forks of bushes. Some mushrooms, thanks to this behavior of Greenland chipmunks, are often found near shrubs where their spores fall, and even form a symbiosis with shrubs.
Mushrooming spots attract some animals very much. The snow porcupine, gorging himself for the future, approaches the bushes in search of mushrooms. Its expectations are not deceived: it finds several bunches of mushrooms in the foliage, and they are immediately eaten. At first, it eats mushrooms growing on the ground, and then, accidentally looking up, it discovers several mushrooms neatly impaled on thorns. The presence of a porcupine is very exciting for Greenland chipmunks: these animals jump restlessly along the branches and chirp excitedly. Ignoring these rodents, a giant spiny beast robs shamelessly their “pantry”: it removes from the branches and eats several mushrooms harvested by thrifty chipmunks. However, there are still a lot of mushrooms, and the animals will find new ones to replace those eaten by an uninvited guest.
Geopossums prefer food of animal origin, although they do not refuse sweet or sour berries that taste pleasant. They are getting very fat for the upcoming winter, put on weight from insects and other animals. At the seashore, it is possible to find a lot of food, and an adult geopossum waddles, carefully examining the surf line. It is looking for dead fish and various marine animals washed ashore by the waves. Near a pile of algae, it senses a smell attractive for it. The geopossum digs up this pile and finds a small dead fish. It grabs the find with its front paws and eats it, sitting in vertical position. After its lunch, smaller predators will get only a bony head and fin remains.
In early autumn, the antlers of skewhorns begin to itch: they are fully formed, ossified, and the old skin falls off from them in patches. The animals rub against the trunks of trees, scraping the skin from the antlers. In the autumn, the skewhorn rut begins. Young males, who have just acquired full-formed antlers, begin to arrange the first trial duels. They are full of enthusiasm, but all their combativeness disappears somewhere when an old beast with a huge antler, sniffing and snorting, passes next to them. The old beast watches them for a few seconds, shakes his antler, and wanders on. He is not disposed to waste energy on the young – he is waiting for more worthy rivals.
A full-bodied mature male bellows, wandering around a group of females. He considers them his own, and marks the boundaries of the harem with urine and manure. If any female accidentally crosses the invisible boundaries of the male’s territory, he rushes to her and pushes her with his shoulders and chest, driving her back to the others. The male regularly mates with females. But he has to drive away rivals who are trying to encroach on his harem in every way. As a rule, these are young ambitious males who clearly do not measure their strengths and claims. They can be driven away by threatening poses and sounds. But the appearance of an old male is a clear challenge to the owner of the harem. He comes to meet his opponent, shaking his head menacingly. Males evaluate each other’s strength by standing side by side: in this way it is easier for them to display the impressive antler to the enemy. From time to time they touch sides, and these touches are not accidental: this is how males evaluate each other’s strengths. Such “duels” can last tens of minutes. If one of the males recognizes the superiority of the opponent, he will simply turn around and leave. Primacy in the herd can be found out in another way: males rear up and bend their heads so that the “counterweight” of the antler sticks high up. Whose antler rises higher, and who will last longer in this position – will win. But if it is not possible to find out the right of superiority even in this way, the fight begins.
Skewhorn males shake their antlers, and then converge head-on. Their butting is mainly a power struggle: the antler of the male lies on the corneous cushion formed by the shape of the shorter antler of his opponent. Different males fight differently: some kneel on their front legs, while others spread their front legs wide and slightly tilt the body. A powerful neck allows a lucky male to knock his opponent to the ground by one head turn. Minor injuries happen if “righty” and “lefty” ones arrange a duel. Then one of the rivals may lack a reliable support, and the antler will slip at the most tense moment.
When mature and old skewhorns are fighting, young males try to avoid the place of the fight: if the fight ends quickly, they may also catch it hot from a heated winner. It seems that two equal rivals have come together in a fight – neither of them is going to concede. The ground flies in clods from under their hooves, antlers loudly knock against each other, and hoarse breath comes from their mouths. Both animals alternately try to knock each other down, but it is clear that the old one loses – without knocking down the opponent at the beginning of the fight, he begins to get tired. And his opponent still has quite enough strength for a fight, and now he knocks the old beast to the ground with a deft movement of the antler. The old skewhorn has been defeated, and he is no longer a dangerous competitor for a mature male. For some time the old beast lies on the ground with his legs stretched out and rests – his sides rise and fall from heavy breathing. Then he slowly rolls over on his stomach and struggles to his feet. It is unlikely that he will encroach on the harem of a mature male, and now his life is turns into a simple existence lacking meaning.
The large mature skewhorn male, literally inspired by victory, approaches his females. Lowering their heads, they show him their submission. But the courtship of the amorous skewhorn is interrupted by other animals. Snow porcupines, a female and a noticeably grown cub, pass near the skewhorn harem. The male, who has achieved success relatively easily in the mating duel, clearly overestimates his strength, trying to drive them away. He displays his power, advances on a porcupine female and her cub, stomps his hooves and snarls nasally. The porcupine female does not understand that the skewhorns have a mating season, and the true motives of the behavior of the skewhorn male are incomprehensible to her. But she regarded his actions as a threat to her cub and started to defend herself. She stands on her hind legs, bristles and bares her incisors. The skewhorn retreats at the sight of an angry prickly giant, and his harem retreats after the master. After running away to a safe distance, the skewhorn male stops and begins to defiantly scratch behind his ear with his hind leg, casting a glance at the giant rodents. The porcupine female calms down, seeing that the long-legged beast, which has something like a snag growing on its head, has moved away from her cub and does not show aggressiveness. She pushes her cub with her muzzle, and majestically disappears among the yellow-leaved birches. The cub minces after her. It is already very large, and strong, jagged spikes stick out in its fur. Porcupines have began to grow thick winter fur, and they are not afraid of the night cold.
The days are gradually getting shorter and shorter. The sun no longer rises so high above the horizon. The time has come for many small inhabitants of Greenland to hibernate. Serpentina eats less actively every new day: it is preparing for hibernation, and the body must be cleansed of food residues, otherwise in winter undigested food will rot in its stomach, and the amphibian may die. Serpentinas hide for the winter in various kinds of shelters: rodent burrows, pits or tree trunks that have rotted from the inside. There are no such shelters in the territory where this serpentina lives, and it is forced to provide herself with a “winter apartment”. With its strong paws and flat head, it rakes the forest floor, burying itself in the loose ground. But this peaceful serpentina’s occupation is interrupted by a geopossum that happened to be nearby. The predator actively feeds, accumulating fat before a difficult wintering, and does not miss the opportunity to kill any living creature that is more or less suitable for food. The geopossum sneaks up to the serpentina, that is busy arranging a burrow, and snaps it by the tail. The attack was clearly unexpected for the amphibian, but the reaction to it was uniform and effective, as always. The serpentina’s skin glands began to rapidly secrete poison, and the amphibian’s skin became covered with a viscous coating. The geopossum, instead of releasing the serpentina and looking for other prey, only tightened its jaws. The result was not long in coming: it burned its tongue with amphibian’s toxin. Unbearable pain pierced the geopossum’s tongue, and after a few seconds, the whole mouth of the predator literally burned with fire, as if the geopossum had taken a mouthful of pepper. The beast’s eyes watered and it released the tail of serpentina, which phlegmatically continued its occupation. But the geopossum didn’t care that amphibian didn’t even think of hiding from it: it didn’t want to eat at all anymore. Another animal of the same size would have been poisoned to death by serpentina’s toxin, but the geopossum has a high immunity to poisons. However, it will have to suffer from a burning sensation in its mouth for several days.
Some inhabitants of Greenland simply avoid meeting with the cold: they just migrate. Songbirds of small species flew to the mainland as soon as the flying insects disappeared, but the crails stayed for a while. Birds peck the seeds of graminoids and catch small animals. They have enough food, and they are in no hurry to fly away. The juveniles train their wings before the migration: the birds take off for a short time and circle in the sky, after which they land into the grass and rest. While the sun still warms, they enjoy life.
But nature lets them know that it’s time for them to get ready for the road. When a thin crust of ice appears on the puddles in the morning, the crails begin to prepare for flying away. They gather in flocks in wetlands, soar into the sky and circle there, both adult and young birds. And one morning, where dozens of birds had gathered yesterday, only a few ones remain now. But they soon leave their homes and fly away.
Crails fly to winter to the south of North America, to the swamps of Florida and even further – to Great Antigua, an island in the Caribbean Sea. They fly in flocks along the ocean coast, making stops at the mouths of rivers.
A few late-arriving birds are feeding on the Greenland shore. One crail is fishing, getting fish hidden among the algae with well-aimed blows of its beak. Its congeners are stirring up rotten algae on the shore, pulling out hidden crabs and snails from them. A geopossum passes by them. It is also searching for prey at the seashore, but these birds inspire respect with the sharpness of their beak and the speed of their movements, and it does not come too close to them. Only from a distance does the beast observe how the birds feed, but it is more expensive to approach them. Finally, having eaten enough, the crails run up, flapping their wings, and take off into the air. The wind caught them, and several huge birds quickly disappear from sight. The geopossum approaches a pile of algae that the birds have been stirring up, hoping to find something edible there. But after the birds’ meal, it gets only a tiny crab, which miraculously escaped the birds’ beaks. And it pinched the geopossum’s finger and managed to escape safely into the water before the marsupial predator managed to bite it.
Autumn has long passed the half. Days are shortening more and more, and at night it is already quite cold, and in the morning puddles are covered with ice. The last withered leaves fall from the trees, and some shrubs will winter being green. Heavy dense clouds come from the north, and soon the first snow dusts the ground.
Northern crails have been roaming the swamps of Florida and Great Antigua for a long time, serpentina sleeps deep in an underground burrow, and numerous insects have huddled under the tree bark or in moss. Skewhorn herds huddle together, protecting the juveniles from gusts of cold wind and warming them with their breath. And lonely wanderers, huge snow porcupines, roam across the plain, having exchanged summer fur for a luxurious white winter coat. They are still visible against the background of bare tree trunks, but they have no one to fear with their strength. Spikes stick out of the thick fur, which will save the life of a porcupine from a predator, but, alas, they are powerless against cold and hunger – two of the most terrible enemies of living creatures in winter.
And winter is coming again. Clouds pour out a thick layer of snow on the surface of the ground, covering the bushes “over their heads” together with the nests of Greenland chipmunks. But small animals remain cheerful even in the cold. They immediately dig a whole system of tunnels in the snow with some exits to the surface. From time to time, rodents visit their “storerooms” for berries and mushrooms. Despite the efforts of snow porcupines and other lovers of free treats, the animals have gathered a sufficient supply of food to survive the cold winter. Greenland chipmunks appear on the snow surface from time to time – they seem to want not to miss the last rays of sunlight this year. The animals are playing and lying in the snow, and at this moment they make an unforgivable mistake: they lose their vigilance. The reckoning comes instantly: a geopossum jumps out from behind a snowdrift, and grabs one of them. The squeak interrupted suddenly – and everything went quiet. Only the north wind rustles in the branches of the trees.
The last short day of the outgoing year lasts only a few minutes: the edge of the sun only appears on the horizon itself, and almost immediately disappears. This means that the new winter has come into its own definitively and irrevocably. The wind howls over the deserted plains, and a blizzard pours snowdrifts. When the blizzard subsides, a cold aurora spreads across the sky over the plains and forests of Greenland.
And again, the animals remaining for the winter are forced to fight for their lives. Not everyone will see the new sunrise. But this night will pass, the snow will melt, and Greenland will become a green land again.

Greenland geopossum (Geodidelphis nivalis)
Order: Opossums (Didelphimorphia)
Family: Opossums (Didelphidae)
Habitat: Greenland and nearby islands; inhabits almost all biotopes.

Picture by Alexander Smyslov

In the process of evolution, marsupials inhabited mainly the southern continents: South America (where, obviously, this group of animals originated), Australia and Antarctica. In the north, marsupials usually did not accustom: they were superseded by placental mammals. But all the same, among the few migrants from South America to North America (when the Isthmus of Panama rose from the ocean at the end of the Cenozoic) there was a common opossum (Didelphis marsupialis) that successfully survived the harsh winters of the Holocene epoch.
Due to its unpretentiousness and great adaptability, this marsupial has learned to coexist with humans, gaining a great advantage over other species of North American mammals. And after the disappearance of humankind, opossums and their descendants took a significant place in the ecosystems of North America. One descendant of the opossum adapted to life in the conditions of the Ice Age, and subsequently retreated north to Greenland. It had lost the ability to climb trees, but became more cold-resistant, large and strong. In this way, the new marsupial beast evolved – the geopossum.
In its lifestyle, geopossum is a universal beast. It is the lack of deep specialization that allows it to successfully survive among the numerous “strict specialists” living in the neighborhood. Geopossum looks very similar to an ordinary opossum, but it has some differences. It has a shorter muzzle and very strong jaws: carrion makes up a considerable part of the animal’s diet. Being unable to catch a large animal, geopossum will willingly finish its corpse, even decomposed to some extent, and gnaw the gristles clean. On occasion, the geopossum picks up dead fish, ravages the nests of land birds and hunts small animals. From among plant food, it willingly eats berries, roots and mushrooms. Its immunity to mushroom poisons is quite large: this animal even enjoys eating some types of mushrooms, deadly even for large mammals, falling into a state similar to intoxication.
Geopossum is a very bad runner: it is plantigrade, and its short paws are armed with long claws. But it is a good swimmer: these animals can also be found at the islands adjacent to Greenland, where they swim or cross the ice in winter. Its tail, useless for terrestrial life, became very short and covered with thick fur. Also, the ears, which only slightly protrude from the wool, have been shortened. The ears of the geopossum are pretty “warmed up”: they are covered with thick wool from the outside.
The summer fur of geopossum is short. It has a gray coloration with blurred cross stripes on the back. The hair on the head has lighter color, and there are dark spots around the eyes. In winter, the coat becomes long, thick and lighter: the stripes on the back disappear, and the spots around the eyes “fade”.
Geopossum has no permanent shelters and is not tied to a specific territory at any time of the year. Therefore, this species treats its relatives only as a kind of annoying obstacle that can be ignored (of course, it happens so outside the mating season, which takes place late in autumn or early winter). It does not hibernate, although in frosts it becomes less active and tries to build a temporary shelter where it waits for the best weather. In winter, in search of food, geopossum often accompanies large herbivorous animals and feeds at their digging places. The hungry beast even eats leaves and last year’s grass.
Up to a month passes between the mating season and the birth of cubs: the female’s body can “conserve” developing embryos until a favorable time. Cubs are born in the second half of winter. Before this event, the female makes a temporary shelter for herself, where she curls up into a ball and gives birth to several underdeveloped cubs. The female has only 4 nipples – this number is less than at the ancestor, but the brooding pouch is much better developed and covered with thick fur from the outside. Such an adaptation makes it possible to grow normal offspring guaranteed, which has a better chance of survival. A geopossum female gives birth to up to 10 cubs at a time, and, like the cubs of all marsupials, they must independently get into the pouch and take the nipple. When the female feels that all the nipples are occupied, she leaves the shelter, leaving the rest of the offspring to die from the cold. The cubs remaining in the pouch grow and leave the pouch by spring, moving to the back of the female. By the end of spring, they can leave their mother for a while, and at the beginning of summer they become independent. In the second autumn, the animals become adults and can bring offspring.

Northern skewhorn (Posttarandus asymmetrocornis)
Order: Even-toed ungulates (Artiodactyla)
Family: Deer (Cervidae)
Habitat: Greenland, plains and bushland.
During the Ice Age, the number of ungulates inhabiting the Earth sharply decreased: the populations of many species were undermined by human activity, and their numbers were insufficient to survive in the era of cataclysms. Only the most unpretentious species survived alongside with those who adapted to the extreme conditions of existence.
One species that successfully survived humans and became widespread during the Ice Age was the reindeer (Rangifer tarandus). In the process of evolution, this species, adapted to life on the snow-covered plains of the Ice Age, spread across the northern hemisphere and actively evolved. One of its descendants was the northern skewhorn, an elk-sized beast that inhabited the plains of Northern Asia, Beringia and North America. It has gained great advantages in a cold snowy climate, but due to warming it has become extinct everywhere. In the warm epoch of the Neocene, this specialized species persists only at the northernmost land, in Greenland, thus representing a relic of the past glaciation.
The structure of the antlers of this species is peculiar. Its ancestor – the reindeer – was characterized by a certain asymmetry of its antlers: at the end of one of them there was a kind of vertical blade. When the climate became more rigorous, the reindeer descendants became larger, and the blade on the antler began to play an important role in the winter existence of the beast: it helped to dig thick snow cover in search of wintering plants. In connection with such an adaptation, the asymmetry of the antlers increased, and the Neocene skewhorn it reached its apex. One of its antlers has become huge; its front part has turned into a wide vertically oriented “shovel” with several jags along the front edge, similar to a rooster’s crest. To counterbalance it, the back of this antler has turned into an equally massive structure, similar to the lobe of an elk antler, but arranged diagonally (the outer edge is raised). The base of this peculiar antler has become wide, and has shifted appreciably to the midline of the head. The other antler is greatly reduced, and is something like a flat “plate” with several irregular jags along its edge. Usually the right antler is large, although “lefties” make about 10% of the population. When the males find out the relationships and butt, the “working” antler lays right on the counterpart’s reduced antler, which in this case performs a protective function.
Due to such structural features, the skull bones are also somewhat asymmetrical: the frontal, parietal and partly occipital bones on the side of the “working” antler have become thicker, and a “stiffening rib” – a vertical bone ridge – runs along the inside of the skull at this point. Such is the skull of a male. Even the brain hemispheres of this beast differ somewhat in size – this is a consequence of the asymmetry of its skull.
Skewhorn females also have “shovels” on their heads, although a little smaller than in males: this is quite enough to shovel snow. Females don’t have to fight in mating tournaments, so antlers in them are lightweight. Sometimes, the posterior end of the antler has a bizarre shape, varying in different individuals. Usually, the antler “counterweight” in them is curved towards the spine, somewhat balancing the head.
Such an “ornament” is not constantly placed on the head of the beast: in the middle of spring, the antlers shed, after which they grow back by autumn, like in all deer. Accordingly, the antler changes its shape with age. First of all, a young animal forms a “shoulder” in the front of the antler, and then, with some delay, a “counterweight” on the back of the head is formed.
Can a previously symmetrical creature become asymmetrical in nature? It can, and there were many such examples even in the human era. In general, any animal is much less symmetrical from inside than it looks from the outside. The skull of whale and beaks of crossbill and some waders are asymmetrical. Finally, flatfish and snails are not symmetrical entirely. Fossils of asymmetrical sessile echinoderms have been found in Cambrian sediments. And in the Neocene epoch, a new example of this phenomenon appeared: the northern skewhorn.
In order to carry its massive “crown”, skewhorn has a strong muscular neck. In a mature male, it is covered with long wool forming a mane – a sign of maturity and high position in the herd hierarchy. The animal’s back is sloping; its legs are long, with wide hooves that move apart when walking on marshy soil (like an elk). The color of the skewhorn’s wool is variable: from almost black with separate white spots, to completely white.
Skewhorns live in large herds, numbering up to 50-60 individuals. The head of the herd is a large male with a huge antler. Females and subdominant males obey it. In the mating season, in autumn, fights occur between males, during which opponents butt heads and display their antlers to each other. Each male has a harem of several females.
The juveniles are born in the spring. Shortly before that, the females begin shedding their antlers actively. After that, the bones of their skulls become somewhat thinner: they serve as a kind of “reserve” of calcium, which is actively absorbed into the blood and is used to strengthen the bones of the fetus. Therefore, a newborn skewhorn already has strong bones and can run fast an hour after birth. Males shed their antlers at the same time as females, but their new antlers begin to grow much earlier. In lactating females, the growth of antlers may be delayed for about a week compared to the dry ones.
The growth of antlers requires the mobilization of all the body resources. To replenish calcium reserves, animals visit limestone outcrops. They break off small stones with their hooves and swallow them, and also eat the soil around these places. On the seashore, animals can eat snails and other animals with calcareous shells for the same purpose.
The juveniles become mature at the age of 4 years. Females bear offspring every year, and in about a third of births they calf twins.

Greenland chipmunk (Arctotamias subnivalis)
Order: Rodents (Rodentia)
Family: Squirrels (Sciuridae)
Habitat: shrub thickets of Greenland.

Picture by Alexey Tatarinov, colorization by Biolog

In the human epoch, some scientists considered squirrels to be real “living fossils” – for 30 million years before the appearance of humans, these rodents existed almost unchanged. Squirrels and their allies have successfully stood the test of time. They survived the severe glaciation of the Holocene epoch, and in the Neocene they are among the ordinary inhabitants of the northern continents, Africa and South America.
A representative of the squirrel family living in Greenland, the Greenland chipmunk, is a direct descendant of a certain species of North American chipmunks (Tamias). In the fauna of the continent, it is one of the relics of the past glacial era. A long time ago, in the process of evolution, this species changed its behavior: for a more successful survival in the harsh conditions of the Ice Age, this species developed a social lifestyle. Of course, if you live in a dense settlement, it is difficult to eat well: there are many neighbors around who do not suffer from a lack of appetite. But neighbors are eyes that can see the enemy in time, and thrifty creatures that carry food into the nest to help survive the harsh winter.
Greenland chipmunk is a squirrel-sized rodent with a short tail and small ears. The summer color of its fur is brown with a white longitudinal stripe on its back, and its belly is sandy yellow. By winter, this species grows thick fur of a smoky gray color.
Greenland chipmunks form colonies of up to a hundred individuals. They build special settlements – “towns” among thorny bushes, clearly preferring hawthorn and Greenland raspberry. A colony can include up to two hundred nests, among which there are many uninhabited ones: each nest is usually used for housing for only one season, after which it becomes a “food warehouse”. The nest of the Greenland chipmunk is a spherical structure at the base of the bush, woven from flexible branches. The nest is made in such a way that it is impossible to pull it out of the bush without destroying it: these little animals weave live bush branches into the walls of their nest. Inside the housing nest, the animals arrange a litter of dry grass, feathers and moss, which are regularly changed. In winter, housing nests are connected with “food warehouses” – last year’s nests – by a network of feeding trails. The animals do not use the old nest for housing, and in the spring they simply build a new one.
In winter, chipmunk colonies appear completely covered with the snow. The presence of the colony is given only by the burrows leading to the surface, where several sentries are on duty. The alarm signal of this rodent is a short shrill whistle.
Like many rodents, this species is quite prolific: the female bears offspring up to three times per summer. There are 4-5 naked and blind cubs in the litter. They grow rapidly, and already at the age of one month they take an active part in the life of the colony, stocking food on a par with adults. Young females from the first brood manage to bring offspring during the summer.
Greenland chipmunk is omnivorous; it feeds on seeds and small animals – insects and snails. When berries and other edible parts of plants begin to ripen, there is a “harvest time” in Greenland chipmunks: after stuffing buccal pouches with seeds, they run from feeding areas to the nest all day, gathering food stocks for the winter. In the “larders” of chipmunks, there are also berries, especially those that do not spoil for a long time: arrowwood, cranberries and rowan. If a chipmunk finds dried berries of other plants, they also fall into stocks. In autumn, the animals harvest mushrooms, pinning them on snags and thorns. Chipmunks hide dried mushrooms, and new ones are pinned in their place. Food supplies are stored in old non-housing nests, which are only slightly repaired for this purpose.
In winter, the Greenland chipmunk is awake, but almost all of its life is spent under the snow. On the surface, these animals almost do not appear. Only when the frost increases, the chipmunk falls into a non-deep winter sleep.
Life expectancy is short: it is rare that a chipmunk will live up to three years. Usually up to half of the young die in the first winter.

Snow porcupine (Aepythizon cryophilus)
Order: Rodents (Rodentia)
Family: Wood porcupines (Erethizontidae)
Habitat: plains, shrubby thickets and sparse woodlands of Greenland.
During the “Great American Interchange” that took place in America after the rise of the Isthmus of Panama from the ocean, relatively few southern species colonized North America. But they successfully passed the “endurance test” and took their places in the ecosystems of the north. One of the southern species – the wood porcupine (Erethizon) – adapted to life in the harsh conditions of the Ice Age, and its large ground-dwelling descendants became one of the dominant species in the northern coniferous forests. And moreover, one more descendant of this porcupine has advanced into the cold glacial steppes, almost to the very border of the glacier covering a significant part of the north of Eurasia and North America. After the end of the Holocene glaciation, when the climate on Earth became even warmer, this descendant of the wood porcupine retreated after the glacier. In the Neocene, this species inhabits Greenland along with other relics of a bygone harsh era.
Neocene snow porcupine is a close relative of the giant wood porcupine from Beringia and the bear porcupine from Mexico. It is a very large herbivore with thick fur, in which many short pointed spikes stick out. Depending on the season, the porcupine’s coat changes its color: summer wool is light gray, winter one is white. The tail is no longer needed for climbing: this is a large bull-sized rodent weighting about 800 kg, and there is hardly any tree in Greenland that can endure its weight. Therefore, its tail is short; having lost the function of the “fifth paw”, it serves for fat stocking. Snow porcupine is a tireless walker; it has wide feet with cornificated “soles”. The claws of this beast are compressed from the sides and only slightly curved. Using them, the animal digs roots out of the soil, scatters snow, and also protects itself from predators.
Snow porcupine is a peaceful vegetarian. It feeds mainly on the leaves of shrubs; in autumn it eats berries and mushrooms. In winter, it digs up snow in search of roots and evergreen shrubs. If the winter is very snowy, the giant rodent migrates to the forests, where the show cover is thinner and it is easier to feed. In the forest, it feeds on conifer needles and digs snow in search of evergreen herbaceous plants; it also can eat bracket fungi. Some porcupines take advantage of the unfreezing of the sea off the coast of Greenland due to the fact that it is washed by a warm Gulf Stream that has deviated to the west. These animals move to the coast, where there is less snow and air is warmer. On the seashore at low tide, they eat brown algae in the littoral zone.
In its way of life, the snow porcupine is a solitary animal; only females with cubs keep together. Usually the animals do not engage in direct skirmishes with each other, but they mark the territory with their droppings and urine. During the mating season (which begins shortly after the snow melts), males can come to the territories of females if their readiness for mating is determined by the smell.
Pregnancy lasts about 14 months. Such a long period is due to the fact that the development of the embryo slows down in winter. There is almost always one cub in the litter, which is born well-developed, sighted and covered with fur. Half an hour after birth, it can walk and moves with its mother. It stays with the female during the first winter of its life – until the new mating season.
Snow porcupines grow and mature quite slowly: they become fully adult by the age of five. But their life expectancy is longer than that of many other rodents: over 50 years.

Northern crail (Rallogeranus borealis)
Order: Crane birds (Gruiformes)
Family: Crails (Neogruidae)
Habitat: plains and wetlands of Greenland.
Greenland of the Neocene epoch is strikingly different from the one that was in the memory of mankind. Eternal ice remained here only on the tops of the mountains, and a significant part of the islands is occupied by wetlands and lakes. A huge number of migratory waterfowl and wading birds spend their summers here. Against the background of the flocks of ducks and geese, very tall, long-legged birds similar to cranes look especially remarkable. But the true cranes died out, being unable to endure the cataclysms that accompanied the change of geological epochs. But some of their relatives managed to survive. These were, paradoxically, representatives of the rail family (Rallidae), very sensitive to anthropogenic impact. But they were much smaller than cranes, so they managed to keep viable populations in limited areas and evolve fast. Their descendants occupied the ecological niche of cranes, becoming the largest wading birds of the Neocene.
Northern crail is the largest representative of a new bird family descended from the rails: its height is up to 180 cm at weight of about 8 kg and wingspan about 2.5 m. It is a migratory wading bird, a relative of the red-headed crail of Northwest Asia.
The body coloration is contrasting: the top is barred black and white. The belly is colored white. The head and the neck are black; males have rings of featherless red skin around their eyes. Beak is white. The skin on the legs is brownish-gray in females and bright red in males.
It inhabits wetlands and plains near rivers, feeding on small animals. Sometimes it eats ground-dwelling rodents. At the seashore, it hunts crustaceans.
It keeps in pairs that are formed for a lifetime. The bird is prone to polygamy; if possible, the male can mate with two females. In this case, the birds rear their chicks together. Chicks are not aggressive to each other.
This species nests in swampy areas. On a dry island, among the grass, birds jointly build a nest looking like a pile of grass. Both birds trample down the grass and add new portions until they get a pile about one and a half meters wide and up to half a meter high. At the top of the pile, the female makes a depression where she lays eggs. There are only 2-3 eggs in the clutch, and both birds incubate them. Parents take care of their offspring, protecting their chicks from predators. Fully fledged young birds differ from adults in the color of their plumage: black color is replaced by brown. The legs of young birds are lead-gray. The juveniles keep with the adult birds until autumn, and even migrate for the winter together.
Young birds fully grow up in the 3rd year of life.
It winters at the Caribbean Islands and in Florida.

Serpentina (Gigataricha serpentina)
Order: Tailed amphibians (Caudata)
Family: Salamanders (Salamandridae)
Habitat: rivers and forests of Greenland.

Picture by Alexey Tatarinov

After the snow melts, the rivers of Greenland overflow their banks, spilling over for many kilometers. After the water recession, a great number of small lakes and swamps remain at the plains, which represent an ideal place for various amphibians to live. Amphibians are more resistant to cold than reptiles, so they managed to take advantage of a short opportunity to colonize Greenland. Among the amphibians inhabiting Greenland, there are frogs and various kinds of small salamanders that settled to the island in the short moments when it connected with the North America mainland. They are similar to their continental relatives, but one species has become very peculiar, turning into a kind of “polar version” of large lizards. This amphibian is a descendant of the poisonous Taricha newt from North America. It is called serpentina for a fleeting resemblance to snakes.
Serpentina is a very large salamander (up to one meter long). It has a very thin body – its maximum thickness is about 4 cm. Legs of serpentina are short, but strong, and bear four digits. Tail is slightly compressed from the sides, and during the mating season, a fin fold grows on it: serpentinas move into rivers for courtship games.
The naked skin of this amphibian is deliberately brightly colored: it is a warning to all predators that serpentina is very poisonous. The skin of serpentina is red with small black spots on the back; its belly is orange. There are a large number of poisonous glands in the skin, the secretions of which have a characteristic pungent odor. When attacked by predators, serpentina intentionally reveals itself: it wriggles violently, making a noise. If a possible enemy approaches almost at point-blank range, serpentina turns over on its back and displays its bright belly. At this time, a poisonous white liquid is oozing from the skin glands, spreading a stench. If an outsider turns out to be too curious or too hungry, it will be severely punished for excessive interest in the serpentina: when ingested on the mucous membranes of a predator, the poison causes a burn. This will not kill the aggressor, but the affected area will hurt for a very long time, and if the poison gets into the eye, vision is partially lost at this time. This method of protection is much more effective than just the death of the aggressor: the experience will be passed on from mother to cubs, and the next generations of serpentines will be safe.
Serpentina spends most of its time on land, preferring to live in wet places. These amphibians especially often inhabit forests and shrubby thickets, where they hunt insects and snails. Serpentina is active mainly in the morning and evening. In summer, at the hottest time of the day, the amphibian hides in wet places, but on a cloudy day it can continue hunting.
Serpentina feeds mainly on invertebrates, although it occasionally supplements its diet with small vertebrates like bird chicks and rodents. It hunts mainly from ambush (usually being buried in leaves), snatching its prey with a sharp rush. In the spring, during the spawning of migrating fish, it often ravages their clutches, scattering pebbles with its paws and getting to fish eggs.
The breeding season in serpentinas comes in spring, when the rivers of Greenland overflow, and the length of the day increases. During the courtship period, serpentinas move into the water, like all other amphibians.
Serpentina has internal fertilization. In addition, this species is viviparous: after a pregnancy lasting about three months, the female bears two large juveniles ready for independent life. For the delivery, the females return to the water for a short time.
In young serpentinas, skin is colored less brightly than that of adults: they have a brown back and a yellow belly. For the first weeks, the juveniles live in water and breathe with the help of feathery external gills. Gradually, the gills reduce and the gill openings close. When the juveniles leave the water, their coloration changes in a few days to the pattern typical for adult animals. This usually occurs in autumn, shortly before wintering, although in the northern part of the range, young serpentines overwinter in the water, coming to land after the recession of water in the northern rivers of the island.
The adult serpentina spends the winter on land, burrowing into the ground. For wintering, it often occupies the holes of small rodents, expanding and deepening them.