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'The Early Therocene, 30 million years PE.'

'Illuminated by beams of daylight piercing through the dark, icy waters of the arctic seas, a female megaprawn--largest of the shrarks-- spawns a clutch of eggs several hundreds of millions strong, having mated several times in the days prior and provided spermatophores by multiple males with which to fertilize her eggs internally. At slightly over two meters in length, the megaprawn very closely approaches the upper maximum size physically possible for a marine arthropod: yet each of her spawn are only a millimeter in diameter, soon to hatch into tiny nauplius larvae carried along by the currents of the open seas. While she fears no creature in this day and age, as the Therocene seas' apex predator, her numerous young drifting along are easy prey for the ocean's many creatures as part of the zooplankton that form the base of the marine ecosystem's food chain. Of these millions of offspring, fewer than one percent will last long enough to reach the size and stage where they become active swimmers akin to typical shrish: and, by the time they reach adult size, a feat taking several decades and dozens of molts, only about two or three of the original clutch out of a hundred million would have survived--fortunate enough against all odds to manage to achieve such a milestone.'

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Formed from the fusion of East Nodera and North Ecatoria, Mesoterra in the Middle Temperocene is home to the descendants of the various species that once called these ancient landmasses home. Of East Nodera, its wildlife are survived by the threepeaked tricorn, an alpine grazer that is Mesoterra's only extant ungulope, and the pinguiphants, semi-aquatic walkabies adapted to forage on Mesoterra's shores.

But small, offshore isles off the coast of Mesoterra harbor some unusual holdovers from an older age. And one such isle is Isla Easnodus on the southwestern coast, where, hidden from the rest of the world, a tiny remnant of its Therocene past continues to linger.

The banded forest streewi (Microstruthiomys gymnorrhinus) is a late-surviving relic of the hamstriches: walkabies adapted for running on open ground. These would eventually disappear as the continents merged into mainland Mesoterra, with their niche more or less being taken over by the podotheres, another cursorial bipedal clade that come to dominate Mesoterra's ecosystem, and later spread far and wide as far as Arcuterra and Ecatoria. On the mainland, the walkabies that did survive were ones that took to the water to become the pinguiphants, but on these offshore islands, the hamstriches shrank down to a miniscule size of less than four kilograms at most, in an isolated environment, giving rise to the streewis.

The banded forest streewi dwells on the forest floors of the island's tropical forests, formed from seeds that were carried over from the droppings of ratbats and pterodents. A small, generalized omnivore, it feeds on fruit, seeds and small invertebrates, and lives in small social groups, consisting of one or two males and up to a dozen females. Mature males are distinguished by their bold, striking markings and broght red bare patches on their faces which they use for social display and to show off to potential mates. Like most walkabies they possess elongated snouts, which, while not as dexterous and pronounced as in rhinocheirids, are still useful tools for foraging for food in the forest floor and undergrowth.

While facing threats from the sky, in the form of predatory ratbats, the banded forest streewi has no enemies on land. As such, their primary defensive strategy is to huddle in groups when startled, seeking shelter underneath vegetation to hide in their shade from the view of aerial hunters. With their sole danger coming from above, they came to forage in small, tight groups, with individuals taking turns to keep watch and alert the group at any sign of an airborne predator.

Female streewis give birth to a single offspring at a time, after a gestation period of about four months. The young are born fully-furred and open-eyed, and remain with their mothers for up to a year at most, weaning at six weeks but continuing to follow her even afterward, learning to forage and take shelter from danger by watching from example. With few enemies and a smaller land space, they grow slowly and breed infrequently, once every two or three years depending on climate and food availability.

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Armadiles, surface molrocks in the "stem-rattiles" branch of the cladistic tree, were among the first of the molrock family to attain large predatory niches in the Glaciocene. Dominating as the top predators of Fissor, the armadiles preyed on walkabies, rhinocheirids and rattiles alike, spreading onto the Gestaltian mainland when Fissor at last collided with the landmass.

But while the armadiles were initially successful, they would ultimately be a short-lived early experiment in the molrock evolutionary path. They had, unfortunately, spread out during the Glaciocene: a time of cold periods and unpredictable weather, which proved to be disastrous to the armadiles when their ectothermic metabolisms made them barely functional on cold days. Their smaller cousins, the rattiles, were able to endure by becoming dormant and subsisting on small insects and invertebrates, but the Glaciocene and its clime was no time and place for a large, cold-blooded terrestrial carnivore to thrive.

The last surviving species would be the armored brushscute (Pilosquamomys minimus), a species native to northern Gestaltia in the Late Glaciocene, 115 million years PE. A relatively small species weighing two kilograms, it ended up outliving the other armadiles due to its size, meaning it needed less food to survive and could subsist on smaller prey like furbils and duskmice as well as a variety of invertebrates. Brushscutes would enjoy a fair amount of success, inhabiting habitats such as coastal shores, grasslands and temperate forests, and hibernated through the cold winters, taking advantage of brief summers to replenish their stores of food as well as breed. With their very slow metabolisms, their gestation periods were equally long, roughly almost a year: at the end of a summer the females would mate, go dormant, and pass their entire duration of pregnancy during a state of hibernation, birthing their young when they awaken next year to a dozen or so already-independent young that nursed only very briefly before leaving for good: an earlier remnant of a trend that led to rattiles eventually fully abandoning lactation only to re-evolve numerous branches of male-centered parental care now that this constraint was no longer a problem.

Unfortunately, the last of the armadiles would meet their end at the final cold snap of the Late Glaciocene, bringing about harsh winters even they in their hibernation would not survive. The smaller rattiles, better able to wait out the cold with fewer needs, would make it through the brief period of extreme temperatures and begin to re-diversify in the Temperocene, with some, such as the garitors and the varats, eventually coming to fill the empty niches of large predators that the armadiles had left vacant.

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The abundance of coral reefs in the tropical oceans of the Middle Temperocene are conducive to the diversity of all sorts of organisms, all specialized and centered around the calcified skeletons of billions upon billions of tiny polyps. Unsurprisingly, where there is coral, there are plenty of coral-eaters: for where there is a food source left unexploited, a niche will, sooner or later, come to emerge to take advantage of the resource and benefit off of ot to survive.

One of the oldest lineages are the clawrrals: an ancient clade of small shrarks that, rather than using their rostrum and pincer pseudo-jaws for seizing and dismembering active prey, instead specialized upon durophagy, crunching up coral with their powerful tripartite "beak" and feeding on the soft parts within. So successful is this clade that they have endured since the days of the Middle Rodentocene, over 130 million years ago. This is, however, not to say that their survival had been stable throughout, as their diversity have been devastated twice, first in the dawn of the Glaciocene when changing water climates led to a significant die-off of clawrral species due to significant levels of coral bleaching in the regions that became suddenly much colder, and another more recent one in the Early Temperocene, when warming seas devastated those that had adapted to the cold: yet, by luck, some species managed to survive and flourish once more.

The genus Chromatocarcharocaris is one of the most successful of these to survive, and today in the Middle Temperocene number in hundreds of species all across the tropical oceans. These brightly-colored reef species come in all sorts of patterns, colors and shapes, with some species radiating out from coral-eating to other forms of generalized durophagy, including bivalves, quillnobs, and even scavenged bones and shells of deceased marine organisms. The harlequin clawrral (C. crayolae) is a typical member of its genus, ranging across Mesoterra's coast. Like many of its genus, it sports bright colors as a warning to predators thanks to its diet of coral polyps with defensive toxins, which it is immune to and even sequesters in its body to make it highly distateful to predators. Some coral polyps, like other cnidarians, have developed stinging cells as defenses, but the clawrrals in turn have developed a high resistance to them, allowing them to consume a dangerous meal few other competition wants to touch.

A specialization to feeding on the abundant corals of the reefs, however, is no longer the monopoly of the clawrrals. As gastropods became ever more successful in the seas, gradually competing more with the crustaceans, several highly specialized ones also emerged to feed on this abundant, rarely-exploited resource. Violet prickpillas (Echinolimax xanthospinum), a member of a group of shell-less marine gastropods known as the slugworms, similar to the Earth nudibranchs. This species in particular is notable for developing defensive spines in place of a hard shell, allowing it to chew away at coral reefs with little concern. Pre-chewed coral with the softer centers exposed are of particular favor to them, causing them to frequent areas clawrrals inhabit and, preferring different parts of the same food, are able to coexist with minimal competition.

An even more unsual gastropod coexists with these: asterisks, six-armed bottom-feeders vaguely similar to starfish. Yet even that passing resemblance has been lost in the peculiar pinball armarisk (Rotundocochleus globulus), which, while still retaining the six-sided shape has now evolved a hard covering on each side, forming a round, orb-like body with its mouth and foot protruding from the bottom, anchoring it to its feeding surface while its radula scrapes away attached algae and other attached microorganisms onto the coral surfaces. When threatened, it retracts its soft parts inward and closes its six plates to form a near-impenetrable spheroid, dropping to the ocean floor as it does so. Once danger is passed, it begins its slow journey back up to reef to resume its feeding.

As destructive as these organisms may sound, feasting upon the very foundation of the reef ecosystem itself, they are, in fact, now very important to the well-being of the tropical coral reefs themselves. Countless millennia of being fed on relentlessly have caused their favored coral species to grow at a much faster rate, and develop chemical defenses that make them less-ideal homes for other small organisms. By keeping these aggressive, poisonous or even venomous stinging species constantly trimmed, they prevent them from overgrowing the reef and crowding out other, more-amicable kinds that are vital homes and nesting grounds to the other species of the shallow seas.

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Some more older Hamster's Paradise fanart I thought I'd share!

Last Bloom and Boulder (How to Train Your Thorhorn?) by @yee-qi

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Diving with the Plurodon by u/Certain-Unit8147

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Always nice seeing my stuff in different art styles. ^_^

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In the Middle Temperocene, the podothere family has expanded more than ever, with various new species of pterodents having evolved once they had mastered the skies and outcompeted the ratbats in larger flying niches, their efficient respiratory and skeletal structures making them better at flight at greater sizes, with some reaching wingspans of slightly over five meters at most.

These adaptations are thanks to those of their ancestors, the cragspringers: mountain-dwellers in the high mountains and plateaus of the Mesoterran Alps, and ones very much still extant today, even amidst the success of their flighted kin. These adaptations of large, multipartite lungs that maximize oxygen intake, hardened tendons that support their skeleton for extra lightweight sturdiness, and patagia connecting their wrists to their hips to help slow their falls when leaping about on cliffs, were ancestral to the pterodents' efficient flight: yet very well still serve their original purpose in the basal non-pterodent cragspringers.

The most remarkable of these basal cragspringers is the alpine tie-lung (Pneumopatherotherium aerobicum): a cragspringer that, unlike its ancestors that were opportunistic omnivores, has become a specialized predator: specifically adapted for hunting larger prey. Pterodents that nest colonially among the rocky ledges of steep cliffs, threepeaked tricorns, Mesoterra's only extant ungulope that grazes on the dense mosses and lichens of the rocky surfaces, and even smaller species of basal cragspringer are all part of the menu of the alpine tie-lung. With impressive stamina, parachuting patagia, seizing talons on its prehensile hind feet, long, strong grasping forelimbs that allow it to grapple its prey, and a long, balancing tail, this specialized hunter is unmatched in its prowess in its snowy mountain home. Its forelimbs, longer than other podotheres, enable it to be partly quadrupedal on occasion when scaling steep cliffs, lying in ambush before dropping on its prey from above with the aim of throwing them off to fall to their demise, letting gravity deal the finishing blow.

But easily the most impressive adaptation of the alpine tie-lung are its namesake lungs: subdivided into proximal and distal segments, the two lungs contain two modified bronchi each that are tied together by large, air-filled chambers on the upper and lower ends, and many respiratory bronchioles branching off from the two main airways in each lung: one going in, one going out. With the help of specialized thoracic intercostal muscles that can inflate the upper and lower halves of the chest cavity separately at different points of a breath cycle, and smooth muscles dilating and constricting the bronchi to act as valves regulating the circulation of air, the alpine tie-lung as achieved something no mammal previously had: a unidirectional airway system not quite to the level but comparable to in some ways to the Earthly avian respiratory system: allowing a single inhalation of air to essentially circulate twice through the lung and be pumped through two separate sets of respiratory bronchioles in two separate breath cycles before being exhaled: doubling their oxygen intake in the thin high-altitude air and giving them an advantage over other animals that must expend extra energy trying to make do with the low-oxygen atmosphere.

Well at home at high altitudes of up to 5,000 meters above sea level, the alpine tie-lung lives a solitary life, only coming together during the breeding season. While of similar sizes, males are distinguished from females by darker markings on their heads as well as black-and-white stripes on their patagia that enable these built-in parachutes to double as display flags, with females favoring males that bear darker and bolder stripes. After a pregnancy of four months on average, a single cub is born at a time, which depends on both parents taking turn to care for it while the other hunts for food. At about a year of age the juvenile is mature enough to start hunting on its own, practicing on small furbils and duskmice to hone its skills before graduating to larger prey, and soon after leaves its parents for good to become an independent hunter, proving that even what appears to be a transitional midway point between a major evolutionary leap is in no way "half-evolved": and able to find a stable niche with its comparatively primitive adaptations even in the presence of its more-derived relatives.

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The proliferation of coral reefs in the Middle Rodentocene, 10 million years post-establishment, has attracted many other sea life to the relative safety of its sheltering calcified structures. Numerous shrish, descended from krill, as well as bivalves, gastropods, and other varied invertebrates fill the coral reefs with teeming life, while immature, neotenic coral resembling jellyfish and anemones, fill the surrounding waters or anchor onto the accumulated coral skeletons that build up over time.

Eventually, as niches in the reef ecosystem began filling out, one aboundant resource remained untapped: the coral itself. One such species to take advantage of this bounty is the azure banded clawrral (Albacyanocaris tralalae), a small, primitive species of shrark whose rostrum and front claws, rather than forming a three-jawed snapping beak to seize smaller shrish, instead becane hard, crushing nutcracker-like instruments suited for cracking apart the hard coral exoskeleton to access the soft polyps inside as well as the algae growing on the surface of the coral. While they consume gastropods and bivalves on occasion, coral constitutes a large portion of their diet, grinding away at the hard reefs and leaving fine particulate debris in their wake: debris that wash ashore and over time pile up to form white sand beaches in tropical regions over the course of millions of years.

Males, growing larger than females in an inverse of the usual arthropod trend, are distinguished by their bold blue-and-white markings that signal to prospective mates their fitness. Their greater size is an advantage when males tussle brutally over the right to fertilize a gravid female, often seizing each other in their tripartite pseudojaws and trying to fling their opponent away or even crush and dismember their rival's claws. Unlike many crustaceans, shrarks' claws are less expendable as they play a part in feeding: and while they can regrow, it is at great metabolic cost as they cannot feed effectively until the new claw grows in. The loss of one claw still allows them to feed with some difficulty, but losing both essentially dooms them to starvation, and significant damage to the rostrum forming the upper jaw will break the exoskeleton of their cephalic segment, with invariably, instantaneously lethal results. Once fertilized, a female will carry her cluster of several hundred eggs with her until they hatch, at which point the planktonic larvae are already able to spread far and wide and fend for themselves.

While acting as regulatory trimmers of the coral and preventing it from overgrowing, the azure-banded clawrral can itself be devastating should it consume too much of its coral diet. This is mitigated by significant predation from other, larger species of shrarks that help keep their numbers in check, but in places where unfavorable conditions lead to local, small-scale declines of their oceanic predators, the clawrrals breed out of control, explode in numbers, and voraciously ravage the reef ecosystem's coral, often with devastating, long-term results. As they exhaust their food supplies, clawrral populations then starve and die off, mercifully acting as a self-control mechanism that curbs their population growth almost like a last resort, albeit with significant damage.

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'Large regions of Mesoterra, shielded from rainfall by the Mesoterran Alps, have become dry and arid in the tropical climes of the Middle Temperocene, aggravated more by its equatorial geographic location. In these places, few plants, typically water-storing succulents, can grow, with the rest being dry, dusty dune nigh-inhospitable for most life. Yet animals thrive here in spite of its harsh conditions, not just tiny furbils or rattiles, but surprisingly large ones too.

The desertdune ratat (Imperiomyotherium lucasi) is an unusual piggalo descended from the twotoned pottalo, that retains its ancestor's four tusks and relatively longer neck for browsing, but has changed in many ways to adjust to its environment. Its long legs, elevating it to a height of six feet at the shoulder, allow it to increase its surface area to volume ratio, enabling it to lose excess heat, and herds seek shelter during the day in the shadows of tall dunes or rocky outcrops, preferring to travel in the cooler hours of dawn, dusk and Beta-twilight. Its leathery hide is covered in thick folds of wrinkled skin, and its eyes and nostrils have protective skin folds to prevent sand from entering them when blown by the wind. Large broad feet to prevent it sinking in sand, allow it to travel great distances in search of food and water, feeding eagerly on the hydrating succulents that can allow it to survive without water for up to two weeks at a time. But in spite of its superb adaptations, it does face a significant challenge: its long legs forcing it to kneel down to drink in an ungainly manner, a posture leaving it vulnerable to predators such as desert-dwelling loupgaroos.'

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Drundles, a lineage of megafaunal boingos that arose in the Late Therocene, flourished in the Glaciocene as a major browser of the treetops, and alongside the grazing hammoths became the most common herbivores of the tundra and taiga. Weighing up to three tons, they were not creatures built for jumping like the smaller boingos, and would become plodding bipedal walkers instead: adaptations that would be adopted by their later cursorial descendants, the podotheres.

In the Late Glaciocene, however, the climate beginning to warm after periods of heavy glaciation, and the biomes beginning to change from tundra to temperate and temperate to tropical, would cause these ancestral drundles to decline, allowing the boom in diversity of their podothere descendants to gradually displace them, being more behaviorally flexible in the smaller-sized niches that the remaining non-podothere drundles were forced into as the larger species died out. The last species of non-podothere drundle, the banded dwarf drundle (Parapodotherium melanoleuca) would persist for some time in the northeastern regions of Arcuterra's coast, adapting to feed on hard, unpalatable toxic plants that podotheres rarely fed on. Like all specializations, however, this would prove a short-term gamble, as generalists are better at adapting to rapid changes in the environment than specialized animals are.

And, in a cruel twist of irony, the basal drundles' ultimate demise would come from a species that technically itself was a very derived drundle: and yet in every way their opposite. While they were slow-paced, peaceful and simple-brained herbivores that bred rather slowly, their hostile distant kin would be agile, violent, highly-intelligent predators who were very prolific breeders. No match for the harmsters' ravenous hordes, they too would fall prey to the end-Glaciocene mass extinction: one that would also claim the hammoths, plurodons, slaybers, thorhorns, splintsters, non-derelict seavers, non-meowse carnohams, and ultimately, the harmsters themselves. While dwarf drundles and harmsters represented two truncated branches of the drundle family tree (unless one counted the unicellular shroomors), their line lives on in the rest of the podotheres, including forms as diverse as loupgaroos, fangaroos, grimhogs, stagotaurs, cragspringers and pterodents, the latter being successful flyers that have become secondarily flightless many times in various secluded island biomes.

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The girats, an early lineage of hamtelopes adapted for high-browsing, produced several unusual lineages in the Glaciocene even as their numbers, diversity and range dwindled. One group that had survived, and fared well across the Therocene, were the giraards: an unusual clade who found a unique use for the long prehensile tongues they used to feed on leaves and branches: to supplement their diet with insects, especially ants and termites, first from the ones that dwelled in the trees, and eventually other mound-dwelling species on the ground.

The girats as a whole would generally not fare well in the Late Glaciocene, as the cooling climes and unpredictable bouts of weather both led to palatable trees dying off and their insect prey living deeper underground. To adapt, many species soon abandoned their crude, unwieldy cheek-horns and battering-ram heads, and switched to digging with their hooves: ones that, in time, lengthened into blunt, shoveling claws that they used to burrow into their subterranean colonies to track them down.

The long-clawed giravark (Giraffamyrmomys longinychus) was one of the last surviving species, and a typical member of the remaining members as of the Late Glaciocene. They thrived in temperate regions of Arcuterra, and became specialist feeders of basically only two food items: the commonly-found descendants of the bombermite, the towering fortresser (Edificitermes multireginus) and the seeds and nectar of the pipeflower brassica (Tuberobrassicus altoflorus).

Towering fortressers live in large, underground networks of tunnels and chambers, with their large, rock-hard mounds being used like chimneys for thermal regulation. As their environments can get rather cold especially during the night, the fortressers insulate their homes with denser walls and build their mounds oriented at an angle to the sun's path across the sky: catching its rising and setting rays to heat up the colony via its chimneys, with the heat remaining inside for longer. Should nights get too cold, they can enter a state of torpor, reducing activity and metabolism to save energy, and resume their progress once the weather warms.

Like their bombermite ancestors, the fortressers have three kinds of soldiers: large-headed biters, acid-squirting sprayers, and self-destructing blasters, all to defend against various different enemies: be it ants, ratbats, insectivorous furbils, or giraards. While the long-clawed giravark has done away with its heavy facial plating, it has not lagged in the arms race: its long snout puts its vulnerable eyes and ears further from its mouth, while the leathery skin on its snout can close its nostrils to prevent retaliating insects from entering. Its thick facial fur make it difficult for the termites to climb its face, struggling to navigate what is to them a dense forest of towering hairs.

The most unusual trait of the fortressers, hoever, is the way they reproduce. Like other termites, a king and a queen are sole breeders in a colony of sterile workers and soldiers. However, queens have a unique ability to lay unfertilized eggs: which, unlike hymenopterans which hatch into male drones, instead hatch into females: genetically identical clones of the queen herself. This ability allows her to produce young without the king's genes: allowing them to be replacement queens the king can mate with should she die, without the risk of inbreeding should he mate with his own daughters. Some of these satellite queens even move out of the colony and find mates from other colonies: ensuring the genes of these one queen are spread far and wide.

These termites have a relationship too with pipeflower brassicas. They guard its roots from underground pests like worms or beetle larvae that target its energy-rich tuber-like roots and fertilize it with their droppings, and in return the plant produces small nutritious growths from its roots in the winter where food is scarce: enticing the termites to keep protecting it as a valuable resource. This leads to it commonly growing within the vicinity of termite mounds: and thus, attracting the attention of giravarks as well.

The pipeflower brassica soon adapted to exploit this too, and fills its fertilized flowers with plenty of tiny seeds, which it then coats in the interior of its flower tubes with sticky nectar. Using their long tongues, the giravarks too feed on the nectar as a source of carbohydrates to supplement their protein-rich insect diet: and ensuring the seeds are spread near other termite mounds in the giravark's droppings when it approaches a mound to feed.

Unfortunately, changing climates in the Glaciocene's end would ultimately disrupt this strange three-way relationship between predator, prey, and a plant that symbiotically benefits both. As the warming climates soon turned much of Arcuterra into savannah and desert, the pipeflower would eventually dwindle, and soon die out. Soon would decline the termites, and with them the giravarks and other giraards too, and while enough of the towering fortressers would survive deep underground to later re-adapt to a drier world, giving rise to the cathedral mites feeding off desert adapted cacti-like grasses called saggros, the giraards would not be so fortunate: and ultimately vanish at the dawn of the Temperocene. Their legacy as specialized insectivores would not end with them, however, as in the Temperocene a whole varied array of myrmecophages would evolve from all sorts of lineages to take their place in the vacant niche, across the many continents: long-snouted zingos, specialized rhinocheirids, dwarf hammoths and various rattiles, feasting on the bounty of insects available during the tropical climate of the Temperocene era.

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'Burdened by her heavy load for the past three weeks, a female alicorn wingle (Ceratosauropteryx monoceros), hidden safely among the branches of a thorny stonefruit bush, finally delivers her precious cargo: a single, well-developed offspring, coated in a sticky sac that adheres to the leaves and bark, and is proportionately very large at birth: already quarter her own size, and half the size of her attending mate. Below, on a lower branch, a second female too prepares to birth her young, her belly so distended that she can scarcely take off and must depend on a male to bring her food. So costly is this laborious effort that the act of delivering the infant is the first and last contact she will have with it: once born, all care now falls onto the male to feed and tend the young until its horn and wings grow in, while the female leaves for good to recuperate from her exhausting ordeal.'

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The Middle Rodentocene: 10 million years post-establishment

Bogs and Kisses: Wetlands of Ecatoria

Ecatoria, the warmest of the continents thanks to its equatorial position and geography, is the site of quite a diverse range of tropical biomes. While much of it is arid desert or tropical savannah, a few smaller patches of other biomes occur in wetter places, such as coastal regions or areas with lower elevations where water tends to gather and flood during periods of frequent rains.

Ecatoria's wetlands, predictably, are a hotspot of biodiversity, with the freshwater habitat intermixed with the land being a favorable and conducive environment for a wide array of life to thrive. Aquatic plants, such as reedgrasses, grow up from the flooded wetland soil, resistant to waterlogged, low-oxygen environments, with their roots and rhizomes acting as anchors to the pond bed, preventing soil erosion. The slow-flowing water in the meantime allows the rapid growth of algae and other pond micro-organisms, providing food for many aquatic invertebrates, such as the water-dwelling larvae of various dipteran flies and amphibious wasps and beetles, which in turn are food for the freshwater shrish, immigrants from the sea that have ventured upstream and made a living in the less saline environment. On the muddy marsh-bottoms, rich in detritus and waste nutrients, shelled mollusks such as freshwater bivalves and aquatic gastropods feed, acting as the wetlands' clean-up crew in recycling byproducts of the food web.

As a broad spectrum of niches became available, a diverse array of hamsters have eventually come to take up residence in this biome. Swamp puffpaddles (Buoyacricetus stagnumus) are among the most common: using their inflatable cheek pouches as flotation devices, they can easily traverse the flooded land as they forage for grasses, seeds and other, edible plant matter. Another frequent sight is the long-tailed muskrew (Coypumimus gymnocaudis), an unusual, semi-aquatic basal shrewbil that, contrary to its insectivorous burrowing kin, instead took up a life at the water's edge, where its omnivorous diet now includes plant matter as well as bottom-dwelling snails and bivalves, which it cracks open with its poweful teeth, or, failing that, by striking them repeatedly against rocks and logs to open its prize.

Another, remarkable resident of the wetlands are splay-footed sprintles (Cursiosaltomys magnapes), small jerryboas equipped with long legs and broad splayed toes to help them navigate the wetland environment. They, most notably, are cursorial walkers and runners rather than hoppers as is the case with most jerryboas, and their distinctive weight-distributing feet allow them to walk on soft muddy ground without sinking, wade through shallow water, and scamper across floating vegetation, enabling them to pounce upon the abundance of flying insects prevalent in swampy areas.

Larger herbivores live in these wetlands too. Swamp cavybaras (Cricetochoerus lustrumus) wallow about these muddy waters to cool off, diving beneath the surface to graze on aquatic plants. These sociable creatures gather in large groups, primarily bigger groups of females that stay close to one small territory, and smaller groups of wider-ranging males that visit different herds of females looking for a chance to mate. Meanwhile, firmer ground is home to diamond-backed swamptelopes (Lagocervimys stagnus), hamtelopes that graze on the firmer land grasses closer to shore. While predominantly terrestrial, they have splayed, hoofed toes that enable them to run across bodies of water with ample vegetation as footholds, enabling them to make a quick getaway when threatened.

And such threats come from unusual predators unique to Ecatoria: unlike other continents, where fearrets dominate the terrestrial carnivore niches, here they are absent, and thus the other main branch of hamster predators takes their place: the hammibals, now larger than the earliest forms such as the huntsters. Some, like the 15-kilogram spotted mudger (Melemimomys variegatus), are predators of other hamsters, with cavybaras, hamtelopes and muskrews being their favored quarry, which they tackle with stabbing, slicing incisors to deal heavy wounds to their prey which they then patiently wait to succumb to blood loss. Other, smaller species, such as banded prawnsers (Pescadorimys crustaceophilus) instead turn their attention to the abundance of shrish in the ponds and streams, becoming skilled swimmers and ambush hunters that seize their aquatic prey with their forepaws and dispatch them with a bite to the head. On this continent, where the hammibals hold monopoly over predator niches, they would, in time, give rise to the hamyenas, a clade that in time would find great success through their adaptable and diverse descendants, the zingos.

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The Middle Rodentocene: 10 million years post-establishment

Whatever The Weather: Northern Tundras of Nodera

The planet of HP-02017 is a mostly temperate one as of the Middle Rodentocene, featuring a wide range of biomes and habitats across its continents and oceans. As the hamsters spread all across the globe throughout the millennia and begin to speciate and diversify, they begin adapting and specializing to each biome, and the many different opportunities and challenges each has to offer.

The northernmost latitudes of Nodera are no exception: despite its treacherous conditions, with temperatures regularly below 10°C and in winter plunging well into the negatives, the hardiest of lifeforms, adapted to the cold, make a living in the frigid temperatures in spite of its seeming inhospitability.

For six months at a time, the landscape is bare and barren: the soil frozen, the plants all dormant, the animals in hibernation until warm weather arrives. But come spring and summer, the flora bursts into bloom, germinating from cold-resistant seeds buried in the ground, and even as the soil above is still partly coated in swathes of snow and ice the landscape is quickly coated in a carpet of green. Among the first pioneers are lichens: hardy fungal-alga symbionts, they provide a ground cover acting as a buffer against temperature extremes, fix nitrogen from the atmosphere, and most importantly, provide food for a wide array of animals, especially during the cold winter months when there is nothing else to eat.

From these lichen-covered grounds soon sprout other vegetation in the form of true plants, such as tufted snowpuff (Arctograminiae spp.), grasses easily identified by their fluffy white floral spikelets, and tundra brassica (Cryobrassicae spp.), descendants of cultivated cabbages now more closely resembling its wild ancestral form. These plants are able to tolerate very cold temperatures thanks to natural antifreeze proteins in their cells that bind to forming ice crystals and halt their growth before they can damage the plants' tissues. These proteins are produced by the plants in response to changes in shorter day length and drier atmospheric conditions: a sign of the approach of winter.

With such an abundance of vegetation in a short span of time, the fauna of the tundra too begin to emerge. The largest of them, the tundra cavybara (Cricetochoerus arcticus), which can weigh as much as 30 kilograms, is a voracious consumer of lichens, grasses and brassica alike, having fasted in hibernation for the cold winter months. During its long sleep its metabolism slows down to a point that its heartbeat and breathing are nearly imperceptible: however, it resumes activity as the weather warms, losing up to a third of its body weight as it uses up all its fat reserves. Groups of up to twenty individuals share the same communal winter den, huddling together to conserve heat, but go their separate ways in the warmer months as they spread out to forage.

Other herbivores take advantage of the seasonal bounty of food, some traveling long distances to access them. Wooly jumpers (Tundrosaltocricetus borealis) are large, shaggy jerryboas, roughly 20 kilograms and weight and standing three to four feet tall, that typically range south in temperate zones closer to the equator, but migrate north to take advantage of the seasonal bloom. Their leaping gaits are highly efficient at covering large distances with minimal expense of energy, and thus they are well-suited to take advantage of the plentiful cold-weather plants. Roots and tubers, rich in stored nutrition, are a favorite of the alpine gootling (Frigicavicricetus arvicoloides), basal gouties that seek shelter among the rocky outcrops of the tundra and dig for underground rhizomes as they forage, with the sugary roots of tufted snowpuff being a particular favorite. Seeds, tough stems, and lichens attached to rocks, in turn, are the diet of choice for white snowsnips (Albucricetus leucis), tiny duskmice whose pale coloration camouflages them against the ice and snow, as well as the abundant white flowers of snowpuff in full bloom.

With plenty of herbivores active seasonally, it comes as no surprise that a local carnivore would take up residence in such prime hunting grounds and thus fill the niche of the tundra's apex predator. The arctic vermine (Cryomustelomys polaris), the most northernmost of the fearrets, is not a particularly large animal, only weighing about two kilograms and reaching two feet in length including its tail, yet it is able to take on prey larger than itself, such as the tundra cavybara. However, it is not very picky, and will take on smaller game as well if it can find them, particularly raiding nests of alpine gootlings trying to catch and kill as many as it can to store them in its den to eat later.

These times of plenty are fleeting, however, and as autumn and winter approach life fades from view and the land becomes icy and barren once more. Plants go dormant, or die off entirely, survived only by their overwintering seeds, and most of the animals begin returning to another six-month slumber, save for the wooly jumpers that begin their long trek south. Within days, as the ice blankets the tundra once again, not a sign of life is visible in the desolate landscape: yet it lies hidden for the moment, waiting to spring back to life when the warmer weather comes.

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In observing the terrestrial carnivores of later epochs, it is easy to draw superficial analogies, with zingos as equivalent to canids, and carnohams as analogues of felines. But in the Late Rodentocene, 20 million years ago, such distinctions were far less clear. With zingos and their broader group the hamyenas restricted only to Ecatoria and Peninsulaustra, the carnohams of Nodera, Easaterra and Westerna filled the niches of running cursorial carnivores: often coexisting alongside other branches of the carnoham lineage in more familiar catlike forms.

These cursorial, pursuit predators are a polyphyletic group, more closely related to the ambush-hunters of their respective continents than to each other. Yet they are united in convergence to their means of hunting: their curved, blunt claws are only partially-retractable, built more for gaining traction while running, while their jaws are longer and open wider, adapted for delivering powerful bites, and slicing teeth to deal wounds to larger prey as they harrass and exhaust them, waiting for them to eventually succumb to blood loss. This is in stark contrast to other, more typical carnohams that pounce on prey and grapple them to the ground, using a choking bite to the windpipe as a finishing move.

The highland leophound (Cynofelicricetus caninailurus) of Westerna is perhaps the most canine-convergent of the carnohams, bearing a short tail, a long snout and pointed ears that make it closely resemble the zingos: distinguished only by its semi-retractile claws and dentition, which remain as two separate cutting incisors rather than merged to form a single piercing point. Leophounds are primarily predators of cavybaras, mostly the smaller species ranging about the 40-60 kilogram range, and while the half-ton giant cavybaras of Westerna are well off-limits as adults, their vulnerable calves are fair game.

The long-tailed dashcat (Velociailurumys pardus) of Nodera's cannonball forests and open grasslands is more of a speed-based rather than a persistence-based cursorial hunter. It chases down its prey, such as hamtelopes or the leaping precursors of the boingos, in bursts of speed of up to 40km/h, using its long tail for balance and its claws to trip up its prey so it can tackle them to the ground and deal a crushing bite to the back of the neck for an instant kill that reduces risk of injury should the prey continue to struggle.

The plains jagsel (Pantheromustelomys longipes) of Easaterra is an interesting case: a more recent evolutionary radiation and within the same genus as the slender jagsel (P. brevipus), a more typical carnoham with a longer body and shorter legs, built for hunting in the mixed scrublands with short, bushy vegetation. Plains jagsels, on the other hand, developed longer legs and less-retractile claws, and are now a distinct species from its more typical relative: enough to the point that they no longer recognize each other as the same species if their paths do cross, and if a rare mating does occur, any cubs concieved are inevitably miscarried or stillborn, their chromosomes seemingly now too incompatible to produce viable young. The two species now have behaviorally diverged as well, as plains jagsels now frequent open grassland where they run down their prey, leaping jerryboas ancestral to the oingos, which are fast, evasive and able to change direction quickly: and so can the plains jagsel, being more agile and maneuverable to capture its prey. A hint to its recent divergence from a traditional carnoham is its killing method, a suffocating bite to the windpipe as opposed to the slashing and crushing bites of other cursorial species.

These species, and their direct descendants, would continue to be successful for the Late Rodentocene and most of the Early and Middle Therocene. However, in the Late Therocene, 65 million years PE, the ongoing collision of the continents would finally allow the different apex predators of the continents to encounter each other: causing increased competition between the zingos, carnohams, Borealian flightless ratbats and the beelzeboars, carnivorous bumbaas that arose in the Therocene. Now in direct competition with the zingos, who had the advantage of social intelligence and cooperation, hunting in organized packs, the cursorial carnohams would eventually dwindle and disappear by the Glaciocene, leaving only the ambush-hunting feline-like ones, and a few aberrant bear-like Early Glaciocene forms. By the Temperocene, the only survivor of the carnohams would be the meowse, a small semi-arboreal carnoham that, over time, would gradually diversify once more, returning the carnohams to prominence on the landmass of Arcuterra.

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The Middle Rodentocene: 10 million years post-establishment

Sunlight at the Okay Coral: Coasts, Reefs and Shallow Seas of the Middle Rodentocene

The Middle Rodentocene is a time of great changes. While in the Early Rodentocene the first rounds of speciation first sprung up, as life first sought to exploit empty niches, now, 10 million years after life had arrived, the various established clades begin to take their foothold in the biomes across the globe, from tundras and grasslands to forest and deserts. But there was one collection of biomes the hamsters had not yet conquered: the sea. However, this was not to say the oceans of HP-02017 were barren, as, aside from just hamsters, a whole other array of living organisms were introduced to support the growth of ecosystems from the ground up: many of them in the oceans. And in the span of time since the beginning, they, too, have been subject to the evolutionary race, growing and changing to fill the gaps left vacant in an incomplete ocean.

Corals and sea sponges, predictably, form the structural foundations of these ecosystems, being filter-feeders trapping drifting masses of phytoplankton and tiny planktonic crustaceans and forming vast, intricate reefs making suitable shelter and habitat for countless other organisms. However, since then, some of the coral larvae have since neotenized, and instead of forming a hard, rocky exterior, have either matured into adulthood as semi-sessile polyps with trailing tentacles for catching food, becoming the anemoids, or evolving into free-swimming forms with transluscent bells, giving rise to the mockjellies. Small shelled sea snails similar to cowries, periwinkles, or whelks, accidental arrivals to the planet from dormant eggs hidden in marine coral, are generalist omnivores that graze on the abundant detritus and algae growing on coral surfaces and the seabed, while bivalves, descended from freshwater mussels, now expand into the seas and converge with clams and oysters, forming clusters on the ocean floor filtering out food particles and playing a role in cleaning the surrounding water of excess organic debris.

The most remarkable creatures of the sea, however, are the shrish: resembling fish, they come in a wide variety of shapes and sizes and number in a thousand or more different species. Some stick to the reefs, sporting brght colors and odd shapes, while others, more silvery-hued, display more streamlined forms and gather in the open seas feeding on plankton. Yet these are not the familiar piscine life of Earth's seas, for they are descendants of krill, an abundant oceanic lifeform forming the bottom of the food chain in their home planet: but here they are faced with no predators, no competition and plenty of vacant niches to fill, and so in a short span of time have exploded in diversity, with some even beginning to swim inland and conquer freshwater environments as well.

On the coasts, where sunlight is abundant, these reefs flourish, thanks to the suns' brilliant rays nourishing the microalgae and phytoplankton that form the base of the entire food web. While the main sun Alpha contributes the overwhelming energy partition, Beta's dim red light adds a tiny extra increment, with some phytoplankton developing dark black pigments as well, to absorb red light so they can continue photosynthesizing even during Beta-twilight.

These micro-producers in turn draw in tiny drifting zooplankton that feed on the phytoplankton, and are in turn food for shrish, mockjellies and anemoids, while algae feed the bottom-feeders of the sea floor, such as the bivalves and the gastropods. A few algae species even form a direct symbiosis with the coral itself, growing inside their tissues and providing then with energy via photosynthesis, in exchange for a suitable home in which to grow.

Such a thriving community with plenty of shrish feeding on a diverse selection of food, would eventually lead to the formation of higher rungs of the food chain. And nowhere would this originate from a fellow shrish itself: with sharp grasping forelimbs, scissoring against a jagged upper rostrum like a three-part, beak-like false jaw, these shrish would evolve to take advantage of the most abundant and unexploited food resource about: other species of shrish.

Known as the shrarks, these predators would only grow to about 9-12 inches at most: but they are formidable predators, ranging across small coastal reefs, where they prowl the crevices to catch unsuspecting prey unaware, to open oceans where they pursue the swarms and shoals of open-water shrish, relying instead on speed and agility. Here, these small, early shrarks are the biggest creatures of the seas: and as time passes, they will only get bigger, as far as their anatomy would allow.

Hamsters, so far, would not have ventured into the seas yet, but on the coasts and shorelines, where food is plentiful, a few experimental lineages make tentative steps into the alluring deep. Basal puffpaddles, swimming duskmice with webbed paws and inflatable extensions of their cheek pouches to help them keep afloat, venture across the exposed tide pools and even plunge into the shallows, to feed on easily-accessible aquatic plants and algae. These coastal species, compared to their lake and river cousins, have adapted to the salinity by developing more efficient kidneys to more effectively excrete the salt.

More specialized cousins of the puffpaddles, the beaver-like pondrats, also roam the coasts and swim from time to time when foraging or escaping enemies on land. These, however, lack the advanced salt excretion of their smaller relatives, and thus are unable to feed or spend much time in the sea, risking salt toxicity and osmotic dehydration if they did so. Thus, coastal pondrats are mostly restricted to the shores, where they supplement their diet with land plants as a source of fresh water, particularly the succulent-like grasses that grow on seaside outcrops which filter out the salt in the water they store inside their stems.

The carnivorous fearrets, too, have made their advancements toward the sea, and now are surprisingly good swimmers, using their long, musteloid bodies and short paddle-like feet to move through the water. While they may opportunistically go after coastal duskmice, much of their diet consists of sealife: while shrish are usually too fast for them, they go after slower sea creatures like snails, bivalves and coral polyps attached to rocks in the intertidal zones when the tides go out. Similar to puffpaddles, they are able to excrete excess salt in their urine, though by preference tend to frequent the open mouths of rivers where they meet the sea, as a source of fresh water from time to time to help flush out the salinity from their systems.

For now, while an abundance of invertebrate life flourishes in the oceans, the hamsters, dominant on land, are only afforded small, experimental tastes of the endless blue world beyond their reach. And as the earliest of the oceans's top predators, frequenting the shores to hunt, comes to recognize these soft-bodied early pioneers as ideal prey, it is a biome that will not yet be theirs for the taking, at least for the time being.

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The Late Rodentocene: 20 million years post-establishment

Lava's Quarrel: The Volcanic Coastline of Peninsulaustra

Peninsulaustra, a narrow strip of land extending westward from the south of Ecatoria, was a volcanic chain of islands that in time fused together into one solid landmass due to the lava flows and accumulation of oceanic sediment over millions of years, and while now a few of its volcanoes still erupt from time to time, many of them are now extinct and dead, having last burst forth lava hundreds of thousands of years ago.

The earliest colonizers of these islands were small, hardy vegetation, such as grasses and lichens, which thrived on the bare volcanic rock and adapted to its unique challenges, developing deep roots to access water, waxy cuticles to avoid dessication, and seeds or spores that could be spread by wind, for while the volcanic islands were harsh, the payoff was the mineral-rich lava flows that allowed the plants to grow quickly and flourish, forming a new biome on their own.

While flying ratbats were, unsurprisingly, the first to make a home here, over time, as periods of cold weather lowered the seas, terrestrial animals from Ecatoria began making their way to Peninsulaustra as well. Small, thick-furred duskmice, such as the peninsular lemlings (Peninsulaustromys minimus) sought refuge among the small crevices amidst the rough igneous outcrops of the solidified lava flows, and larger animals arriving later would graze on the abundance of volcanic flora that had established everywhere in great quantities. Some, such as the igneous rodhog (Volcasuimys igneus), an early member of the bumbaas, forage on the roots, leaves and lichens of the lava flows, as well as frequenting beaches and shorelines to supplement their diet with washed-up algae and kelp and occasionally even shellfish and carrion if the opportunity presents irself. Meanwhile, higher up on the clifftops, where tougher yet lusher grasses grow, small hamtelopes such as the lavarock hamtelope (Magmacervimys pyroclastus) graze in small herds, their flexible toe hooves enabling them to be very surefooted in the uneven rocky cliffs as they climb and leap their way to plentiful clusters of their favorite food.

The primary land predator of the volcanic coasts is the flowland mousehound (Volcanocynomys vulpes), a small, fox-sized zingo, one of the earliest members of its group. An adaptable and opportunistic hunter, forager and scavenger, its diet includes a wide range of varied prey including small invertebrates, coastal marine life, small ratbats, lemlings, and young, sick or old rodhogs or hamtelopes, though healthy adults are well out of its league. Sociable creatures, the mousehound is gregarious, and lives in family groups of up to a dozen individuals: yet each mostly hunt and forage alone, bringing back any excess food they found to the den and sharing them with other members of their pack who had a less successful day.

Eventually, over time, tundras and taigas would eventually come to dominate Peninsulaustra: and these early pioneers would spread out in the Therocene: the rodhogs becoming ancestors to the large herbivorous yeks, and the mousehounds would grow into larger, lupine forms such as the polar zingo. But unfortunately for them, at the end of the Therocene, the increasing cold and continued southern drift of Peninsulaustra would ultimately leave the continent a barren, frozen rock: spelling the extinction of all its terrestrial plant and animal life. Not all would be lost for Peninsulaustra, however, as in the Glaciocene, a new clade would colonize the island and fill it with life once more: the blubbats, flightless ratbats that would seek their food in the sea, with none to be found on the now-frozen continent.

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The Late Rodentocene: 20 million years post-establishment

Glade To Be Here: The Conifer Glade of Borealia

Isolated from the rest of the large landmasses, the small, northern continent of Borealia has, in twenty million years' time, became a site for evolution to progress in a path separate from those of the rest of the continents. While Nodera, Easaterra, Westerna and Ecatoria were interconnected by land bridges on and off, allowing the first hamsters as well as their larger descendants to interchange and spread between them, the continent of Borealia remained unreachable by most of those species: save for a few that came by sky or sea.

Borealia, as of this time, is predominantly covered in a sparse, open forest of conifer trees: ones well adapted for the cooler temperate climate up far north, their seeds brought along by the droppings of ratbats. Its ground cover dominated primarily by grasses, whose feathery, floating seeds drifted by wind to the island, what arose would be a thriving and lush ecosystem that would bring many more fliers from the skies to see this land as an ideal place to roost, and eventually, take up residence permanently.

Notably, many of its niches are now filled by ratbats that have become much more competent on the ground than other ratbats from other continents. With no enemies on the ground, they became more adept at foraging on the ground: most other ratbats being sprawled and clumsy when grounded and mostly hung upside-down from trees, the ratbats of Borealia began adapting to fold their wings more neatly and support their weight more erect, enabling them to walk, and even run, quite decently on the ground.

Some, such as the yellow-bellied pineflyer (Coninyctus borealius) eat primarily seeds from pine cones, and are still good flyers, soaring from tree to tree in search of their nutritious seeds and fruit. However, they have become decent climbers and runners as well: perching on branches with all four limbs, or scurrying across tree trunks and tree limbs with the proficiency of their distant, arboreal cousins, the squizzels: a clade that is notably not present here.

While some ratbats still spend time in the air, a few have begun specialising on a more terrestrial lifestyle. White-winged landbats (Terranyctomys pteralbus) are primarily grounded foragers, which now rarely take off unless startled. They burrow in small dens in grasslands or under logs or rocky outcrops, searching for seeds, fruits, or insects and other small invertebrates, which they carry back to their dens in their cheek pouches to store and eat later, or share to other members of their groups. Highly gregarious, they use their pale wing membranes now as a form of communication, flashing them to other white-winged landbats to alert them of food, danger, or to warn off rivals from other groups intruding into their territory.

While mostly terrestrial, white-winged landbats have not lost their power of flight entirely, as, in the span of but a few million years, another ratbat would in the meantime become the continent's first terrestrial predator: the leopard catbat (Pardonyctomys borealis). This species, with no enemies of its own, has fully abandoned flight: and conversely, inhibited other prey ratbats from doing so. Weighing up to five kilograms, this small underbrush hunter preys primarily on other species of ground ratbats: as well as the various furbils and duskmice that arrived onto the continent by rafting on floating vegetation.

The furbils and duskmice would arrive onto a land now threatened by ground hunters by the time of their arrival, so they would in turn evolve defensive adaptations that lessened their chances of becoming a meal. One group, the heckhogs, would be fortunate to be armed with painful quills that can fend off an attacker, and thus in one species, the Borealian pricklehog (Echinodorsus borealis) they would develop long, barbed spines on their back that broke off easily once embedded in their attacker: proving a very effective deterrent not only for the flightless leopard catbat, but also the other flying ratbats that are also opportunistically predatory to small animals as well. Other species, like the furbils, would instead resort to speed, evasiveness or gregarious behavior as defenses. Firecracker brushtails (Borealiomyocricetus longicauda) forage in groups, and explosively dart in all directions running in erratic zig-zags when threatened, in an attempt to confuse their attacker. Even if such a trick fails, the predator is forced to choose one, giving the rest a chance to eacape and reducing the odds that one individual will be the one targeted by the attacker.

But so far the strangest animal on Borealia yet is its currently largest: hamtelopes that, quite peculiarly, walk not on their two central toes, but on a single toe in the middle: forming an uncloven equine-like hoof. The banded spurfoot (Centrungulopus zebroides) was an unusual hamtelope species that migrated to the island during a brief period of glaciation that lasted only a few thousand years, yet was enough for several hundred individuals to make it across the bridge before it sank once more. These goat-sized grazers would quickly become established onto the island and soon grow in number and spread across Borealia: to the point that their increased grazing pressure would cause the local grasses to develop increased defenses. Some would begin to deposit sharp silica crystals into their tissues, leaves and stems, making them painful for herbivores to eat: and soon an arms race would begin, one that in time will eventually escape the confines of Borealia and be waged across the globe.

Borealia, soon would become the birthplace of many clades and species that would play greater roles in the eras yet to come. The silica-laden grasses would become the saberleaf, a highly-invasive grass that would in time cause mass destruction across the landmasses, while the spurfoots would give rise to the ungulopes: the most successful and diverse terrestrial herbivore clade in the Therocene, Glaciocene and Temperocene. And while the catbats would become precursors to the endemic flightless predators of Borealia, other groups of ratbats, more competent on land than their forebearers but retaining flight, would spread back out beyond Borealia and gradually drive back the basal forms of sprawled-limbed, hanging ratbats: older forms that would become nocturnal to escape their competition and become the night-flying dingbats.

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