Tribbats of the Ultimocene

Descending from ancestors once very similar to the first canitheres, some 75 million years ago in the aftermath of the Thermocene-Pangeacene boundary a very unique tribbethere clade began to diverge. Over tens of millions of years their long legs shortened. Their arms grew muscular, while their fingers elongated to grasp and cling as they left the ground in search of prey that fled the ground for safety in the trees. They became smaller, more nimble and better suited to weave through the foliage, first climbing and then leaping through the trees. They hunted small vertebrates, then flying insects. Membranes of skin formed between their wide spread fingers, forming a sort of net that they cast over their prey to pin them against tree bark - and over time, they found use in these webbed hands to slow their descent when dropping down upon their prey from a height. A flight stroke developed from the prey-grabbing motor pattern, as their fingers became longer still and the webbed membrane provided lift, letting them cross further and farther distances in their leaps to catch their food. On the hind limb the central toe receded and became vestigial whilst the secondary digits rotated to become opposable so that the creatures could roost by clinging upside down in the trees, cutting their ties with the ground further. Countless accumulative small adaptations, each building on its predecessor, slowly turned paws into hands into wings... until at last sometime around 40 million years ago the tribbats leapt from the trees, spread their arms... and took flight, the first new vertebrate group on Serina to evolve powered flight in its history.

But the first tribbats were weak flyers. Their wings were short and broad and served only enough to flutter them between short distances in the trees to catch their insect prey, and their long grasping tails trailed behind them awkwardly. They were, however, good climbers and spent the majority of their time in the jungle canopy where they found an abundance of food. Their wings now took up five of their seven digits on the forearms and grew off of a long spur on the wrist that allowed them to be easily folded up behind the arms when not needed while the two free claws remained strong to provide a grip on the branches. Yet as they became competent climbers they became less and less adept at walking - and ever more ungainly on the ground. This in conjunction with only minimal flight ability - hampered at first by heavy bones and awkward, bulky wings unsuited to prolonged flight - the tribbats remained relatively restricted in range for tens of millions of years to the tropical forests, where their expansion was limited by the presence of dense crowned forest within which they could travel.

Primitive tribbets in the Pangeacene nonetheless explored several diets, expanding from meat toward fruit and from there to leaves and shoots, with some species growing large and bulky and almost fully flightless again to accommodation the large stomach necessary to process such food. Certain relatives of these arboreal herbivores adapted from there on to a very different diet; they started feeding upon the abundant ants' nests that were almost as numerous in Serina's jungle trees as leaves. The huge stomachs reduced in complexity as a diet of ants provided many more calories for almost no additional effort - they filled almost every tree like fruit lying just beneath the bark - and even their stomach acids dwindled for disuse, as ants came with their own formic acid to break themselves down in the gut once crushed by the jaws. Thick skin underneath a plush coat of hair protected them from most bites and stings. Their extensible jaws became sturdy and they gradually evolved a strong bite force at the distal tip of their jaws rather than the back of the mouth as in canitheres; large, blunt incisor teeth became hammers to smash against ants nests underneath bolls in tree bark, after which the jaws retract. A tongue as long as the animal's whole body is then slid between a groove in the upper teeth and licks up the nest's contents, particularly the fat-rich larvae. Aptly named barkbiters, several such ant-eating specialists across two genera are now found across central Serinarcta, all of which are now almost entirely secondarily flightless; too heavy for sustained movement in the air, the most they can accomplish are a few labored flaps from a high branch to a low one - scarcely more than a controlled drop.

a mottled barkbiter bites open an ant's nest in a rainforest tree before licking up the ants and larvae inside; it feeds quickly, for it will take only moments for other cooperative colonies in the tree to be alerted and come to the aid of the damaged nest, at which point the troublesome tribbat must launch off with what remain of its stumpy wings and clumsily fumble into an adjacent tree where it begins the sequence again. Almost all of its waking hours consist of biting open nests, feeding before the ants become too aggressive and moving on, traveling upwind so that the ant trees cannot warn one another of its approach with distress pheromones. Because it can rarely feed for more than 30 seconds at a time, each nest usually survives and can repair the damaged nest structure with fragments bark and adhesive saliva in a matter of hours.

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While such early evolutionary experiments have found some success in the Ultimocene, it was the tribbats which didn't radically alter their initial diets, those which remained carnivores, which would ultimately go on to bigger things. Only the selective forces forged by the arms race to catch ever more nimble, agile prey would eventually favor the right combinations of adaptations necessary for strong, sustained flight and allow the tribbats to at last break free of their ancestral tether to the forest and colonize the world.

The first tribbat wing structure was a membrane connecting the five flight fingers to the abdomen extending down most of the tail almost to the toes and supported from the elbow and the ankle by rods of cartilage. This formed a wide, bulky, but stable wing at substantial cost to agility and flexibility. In order to adopt faster and more controlled flight would require limiting the extent of the wing membrane so that the hind leg could be pulled under the body and reduce drag. Only ten million years ago did a tribbat species overcome the original constraint of their wing shape, and through a single chance mutation formed a clade that would go on to change the trajectory of tribbat evolution forever with a sudden mutation that split the wing into effectively two membranes; the wings, which now attached higher up on the leg or even on the body and were supported primarily by the cartilage rod growing from the elbow, and a tail membrane formed by skin stretched between two now-free-standing cartilage rods that formerly gave strength to the rear of the wings. The narrower wing shape provided much greater maneuverability in the air, while the tail - now freed from the wings - could fold under the body in flight to reduce drag, with the tail fin extended to assist in turns and landing. These forms could fly much more swiftly through vegetation as well as turn faster in the air in pursuit of prey animals. The more advantageous wing shape opened up new niches as active predators, and as strong flight became more advantageous increased selective pressures developed toward the evolution of more powerful breast muscles and an enlarged keel on the breastbone on which to anchor them. The result was a full transformation of the tribbat from a clumsy tree-bound climber into a fast and powerful predator of the skies, and allowed them begin to expand their ranges outward from the densely vegetated tropics to the more open temperate forests and beyond; they colonized all manner of new habitats and spread across virtually the entire world, save the most isolated islands, by the start of the Ultimocene. From that first mutant tribbat ten million years ago the clade has now exploded exponentially in diversity to more than 500 species. Today these free-winged tribbats with tail fins already make up approximately three out of every five species on Serina despite having existed for only a fraction as long as earlier families, and virtually all of those that occur outside the northern rainforest belong to this more derived clade. These are the Dividoptera, or split-winged tribbats.

Dividopterans

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Dividopteran tribbats evolved as predators, but the diets of these winged hunters can range from tiny flying insects up to birds and even vertebrates as large as circuagodonts. Their freely-moving wings and folding tail fans give them high maneuverability equaling that of flying birds and at small sizes their wing, formed from the entire hand, is even more flexible and thus energy efficient in the air. A good indicator of a clade's adaptability and its prognosis for lasting evolutionary success is how widely varied its members are in body size, and in this respect the dividopterans do very well, ranging from less than one-tenth of an ounce to more than ten pounds.

Some of the largest dividopteran tribbats of the early Ultimocene are members of the subclade Volanvenators (flying hunters). This is the oldest subclade of split-winged tribbats, comprising 120 species, and is the group from which all other dividopterans descend, making it paraphyletic for our intents and purposes here. Highly agile flying carnivores that are active by day and hunt via excellent eyesight, they swoop down on their victims on the wing and snatch them up with their projectile slinging jaws. Their mouths operate similarly to those of the canitheres, designed to grasp while extended and hold prey tightly between the teeth when retracted, but they lack the chewing mechanism and swallow their food whole in gobbets torn with the incisors. Originating in forests where their narrow wings let them soar and weave through brush and obstacles with ease, this is the home of the largest of all flying tribbats, the aeracuda: ten to twelve pounds of heavy muscle, with a vicious toothed jaw and a six foot wingspan.

the aeracuda, pictured preying upon a small placental bird, is the heaviest flying dividopteran. It is a large predator with a fierce set of teeth that kills its prey on the wing but which has also adapted to walk quickly and efficiently over the ground better than any tribbat before it.

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The aeracuda is a highly effective solitary predator which feeds entirely on warm-blooded vertebrates up to two times its own body weight. It hunts open forests across both southern Serinarcta and northern Serinaustra, spotting for prey from a hidden perch in a tree with its keen eyesight that picks up any sign of movement. When a placental bird, a molodont or even a small circuagodont appears in its its sights, it pulls in its wings and dives in pursuit. It turns and drops, rises and falls in the air to narrowly miss branches and tree trunks without missing a beat, all the while keeping its gaze locked on its target. Faster in the air than anything can run, jump or climb on the forest floor or in the branches, the chase is a deadly race whose winner is usually determined only by whether the prey can take cover before the aeracuda catches up. If the victim finds shelter in a burrow, a hollow tree, or a dense thicket at ground level then the aeracuda pulls back - it will not attempt to dig out a meal or go face to face with a defensive set of jaws. No, the aeracuda wants a clean kill. It wants to trail its prey, close its long fanged jaws on the back of the neck as it still runs, and knock it down from behind, keeping the jaws well away from its own face as the victim's brief struggle dwindles and the life leaves the body. If the prey is small, it may simply hoist it off the ground and carry it to a tree perch to feed, but if large it simply cuts into the abdomen with its serrated knife-like incisors, and feeds there on the spot. It opens first a small wound through which its narrow pointed jaws can reach in to remove first the choicest organ meats. Later as the initial wound is expanded, its wider cheek teeth will shear the muscle from the sinew and bone so that when the predator has filled its stomach little more than a hollow pelt - a literal bag of bones - lies on the forest floor. After a large meal the aeracuda is often too loaded with meat to take flight, but this is not a problem. With a sturdy first finger adapted to bear weight and wings that support the body nearly vertically on the ground, the aeracuda is the best adapted to walk on solid ground of all tribbats, and merely strides to the nearest tree and reaches up with the wing claws to climb up and rest laying upon a branch - it has become too heavy to hang upside down by its tail alone.

Territorial by nature, the aeracuda comes together only seasonally to breed, and does not form enduring social bonds; as in most tribbats, the male and female partake equally in their care of the offspring which are nurtured in a nest of sticks secure in the crotch of a tall forest tree. For the first month the young, born in broods of two to four, are helpless, blind and deaf and dependent on having one parents in the nest at all times to provide warmth and protection, but afterwards maturity is rapid. By six weeks the pup can fly and by two months of age it is largely independent. Independence and flight ability greatly precede maturity, and the pup grows for up to three years following its independence, during which time it hunts first insects and small birds and gradually progresses to larger prey. meanwhile, the quick maturity of the pups allows the parents to rear several broods per year.

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Other volanvenators have moved out of the forest entirely and adapted to feed on totally novel prey. One such species is the tribbfisher, a tern-like tribbat that has specialized to use its extensible jaw to catch fish and other aquatic prey from the surface of water. Unlike the aeracuda, this species is social to the point of gregariousness and lives and breeds in flocks hundreds strong, hunting out on the shallow ocean waters, inland waterways and coastal tributaries and roosting on sheltered sandbars or islets offshore. With a very wide range covering all of the inland sea between the two major landmasses as well as adjacent rivers, several subspecies as well as related forms exist, all of which are similar in behavior and distinguished primarily by markings.

The tribbfisher has experienced success even competing among seabirds at least partly because it has evolved specialized eyesight that blocks horizontally polarized light, meaning that it does not perceive the glare of sunlight on water as do most animals, including humans. Instead, thanks to a series of microscopic, vertical lines of dark pigment on the surface of the lens of the eye that filter out the vast majority of this horizontally-oriented reflected light from reaching the iris, the surface of the water appears as a clear window even under direct sunlight conditions. Indeed, due to their superior eyesight, seabirds will often follow tribbfishers to find shoals of fish obscured by reflections on the water that they would otherwise be likely to pass by.

Light in weight but wide of wing, the agile tribbfisher is a very social piscivore that lives in large flocks and hunts swimming animals just below the surface, using its protracted jaws like tweezers to pluck out unwary prey which is then swallowed whole.

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Tribbfishers are a unique case of a tribbat that no longer perches in trees, but which has also not adapted well to walk on the ground, despite breeding on open sandy beaches. As all of their hunting is done on the wing and they shelter on islands free of ground predators, they have had little reason to evolve an upright gait or stronger weight-bearing digits like the aeracuda. Instead, when landing the tribbfisher simply lowers its tail and then falls onto its wrists with its wings splayed to the sides and crawls almost on its belly. Parents alternate guarding a single pup, with one always brooding over it to provide protection from flying predators, and many pairs rear their young in close contact for group defense. As in the aerocuda the young matures quickly and reaches independence before being fully grown, allowing the parents multiple annual breeding opportunities. Social year round, tribbfishers are very affectionate with one another and engage in frequent social grooming and physical contact with others - and not only their mates. They are not socially monogamous for more than one season, nor are they sexually monogamous at all. Extra-pair copulation is the norm and bonded pairs exist only to ensure the survival of the young, though very rarely does a male raise only his own offspring. individuals may even switch partners between broods in a single year. While this may seem inefficient it ultimately maintains peace and improves the reproductive success of all individuals in the colony, as no male can be sure that another pairs' offspring are not his own. This prevents infanticide, which could otherwise occur in scuffles over limited nest sites, and may also result in unpaired or even unrelated males lingering around the colony and assisting in feeding the chicks of pairs who have lost one or both parents. Females, able to be certain whose chicks are their own, are much less obliging to adopt others.

Though very poor at walking, the large wings, powerful hind leg and light body weight of the tribbfisher mean that if threatened it can vault itself into the air instantaneously and take flight, with no need for any running start as is often necessary for the larger aeracuda on the ground.

The volanvenators may be diurnal hunters, but from them two other clades have diverged which have become nocturnal, resting during the day and feeding after dark. This has allowed these species to exploit food sources unused by their competitors, and has resulted in several interesting new adaptations.

Only distantly related to the aeracuda or the tribbfisher, the moonbeast is one such nocturnal tribbat which has evolved a highly distinctive appearance as a result of specializing as a primarily auditory, rather than a strictly visual predator. And to do this, it has developed extraordinary ears that form a nearly complete disc around its face, channeling sound down to its ear opening like a satellite dish. Like an owl's, its ear holes are asymmetrical, the right lower than the left, which improves its ability to identify the direction of sound in three dimensional space.

A very large tribbat, second only to the aeracuda and weighing up to eight pounds, the moonbeast is a formidable predator. It is adapted to hunting in some of the the darkest environments on Serina - forests at night, where the planet light that often illuminates the sky enough to see by in more open settings is all but totally masked by the canopy of leaves above. With several species primarily native to northern Serinarcta, the moonbeasts are adapted to locate, catch and consume - whole - prey in almost total darkness entirely by sound. It hunts from a perch, turning its head from left to right until it catches a noise and then pinpoints the precise location a tiny rustle in the leaves or thump on a log originates from. When it has mapped the location in its mind, it swoops down, drops onto the source of the sound and pounces. If it has pinpointed the source correctly, it will close its especially wide jaws over some small molodont that emerged at precisely the wrong time from it burrow. With a gape that can swallow a prey item twice the diameter of its own head, the moonbeast has little need to chew and so its teeth are less specialized than in many other volanvenators; little more than conical points that provide a firm grip.

With an eerie, spectral appearance heightened by the wide disc its large ears form around its skull-like face, the moonbeast is a most unique tribbat. It is the tribbat equivalent to an owl and hunts small molodonts and other tribbetheres in near pitch black conditions.

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Solitary and territorial, they give birth in tree hollows lined with soft mosses. Males do not take any part in child rearing in this group - the mother rears her offspring, usually twins, entirely on her own. Her young are thus born more developed than most, with fur coats that keep them warm as she hunts in the long nights. They fledge at only four weeks but depend on their mother unusually long, up to five months, perhaps because hunting by sound takes considerable practice to perfect than hunting by sight.

The stark white face and red eyes of the moonbeast serve as a warning signal. The face shows the presence of a rival at a far distance in low light conditions, allowing individuals to avoid one another, and the bright red irises of their eyes against this backdrop - combined with a wide hissing jaw full of teeth - provide a stark threat display toward predators that might disturb one roosting in its nest by day.

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The second primarily nocturnal group of dividopteran tribbats is quite different from the moonbeasts, less specialized but more widespread. Though they hunt by night, they do so in more open environments where planetlight or starlight still illuminate the sky sufficiently to see and so they remain visual predators. Though not closely related to the moonbeast, they are generally allied by similarly wide mouths and are equally are adapted to swallow food whole in large gulps. Most forms are bat-like and catch large flying insects on the wing, but two notable outliers exist which will be covered here: the flapsnapper, and the night-biter, two closely related species which have evolved into a prey and predator relationship with a very unusual twist.

The flapsnapper is a medium-sized tribbat with an extremely wide range over most of Serina north of the inland sea. Weighing just over one pound and with a maximum wingspan of two and a half feet, it is not a small tribbat but nor is it close to the largest. Habitat is of little importance to the flapsnapper, which hunts in the air well above the ground, and so can be found by day roosting in trees in forests or under rocks or even in burrows in plains and even arid regions. All that matters to the flapsnapper is that there be a readily accessible source of food to eat... and insects alone will not suffice to sate its hunger. Though it descends from insect-eaters, this form has become a specialist bird- and tribbat-eater. With jaws that expand far outward rather than forward, it easily swallows prey up to half its own weight.

With large eyes, maneuverable wings, and a massive mouth, the flapsnapper catches and swallows whole birds and smaller tribbats on the wing.

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Climbing through branches at night with its curved wing claws it snatches any small flyers it finds sleeping from their roosts, and hunting at high altitudes at night it ambushes flocks of migratory birds, dropping from above and often catching and swallowing several in quick succession. Occasionally, it may also swoop and devour small tribbets, large insects, and occasionally even immature specimens of its own kind. Yet on the open, tropical grasslands of Serinarcta it has a preference for a very specific meal... one that can be especially nourishing.

For it is here, on these open grasslands, that can still be found some of the early Ultimocene's most incredible and bountiful assemblages of megafauna. Herds of circuagodonts proliferate millions strong, chopping the grasses and herbs in their tree-trimmer jaws. Towering above them are the last of the serezelles - enormous, rumbling boomsingers - that plod along like mountains come to life. Weighing over fifteen tons and standing fifty feet tall, they browse along scattered trees without worry, protected as they are by their sheer enormity from any and all predators... or so it would seem.

In fact, in the past million years, the boomsinger has found itself dealing with its first true predator in over ten million years. It isn't a circuagodont with sharp cutting teeth, however, nor a fast canithere or a large grappler with hooked tentacles. No, this enemy is smaller, seemingly insignificantly so to such a behemoth. And this is why it is so successful. You see, the only current predator of the boomsinger birds is a parasite; a two-ounce tribbat called the nightbiter, which has evolved to eat the boomsinger alive.

The nightbiter is very closely related to the flapsnapper, the two species having diverged only four million years ago. While the latter grew larger into an active predator, the former stayed small and found a ready source of food in the form of tick-like parasites - giant mites - that plagued the skin of large animals. For at least a million years this was a mutual arrangement, with both parties benefiting from the partnership... but eventually the ancestors of the nighbiter became bolder. More efficient than waiting for ticks to collect blood was to enlarge the small wounds made by the parasites and drink the blood freely. The creatures also turned to congregating along existing wounds, biting the flesh - even richer than the blood - and preventing healing. They over time grew more powerful jaws and sharp teeth to cut through the thick skin of the large animals themselves. The teeth grew wide, triangular, and razor-sharp, so that the jaw could be protracted to dig them all into the flesh on the back of an animal. Then, when the jaw was pulled back, the teeth neatly scooped out a mouthful of skin, fat and muscle almost as big as the biter's own head - an incredibly rich meal. Today the nightbiter has become a terrestrial equivalent to the cookiecutter shark, a small flying animal that subsists entirely off of pieces of flesh bitten off of a giant living host.

using its specialized cutting teeth and rounded jaw, the nightbiter feeds on living boomsinger birds, eating them bite by tiny bite.

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For a predator weighing an eighth of a pound, 15 tons of boomsinger provides quite literally limitless food, and flocks of the parasites can easily become a bane to the giants. They emerge from their sheltered hiding places by night - sometimes roosting by day even the folds of skin in the arm pits of their hosts - and fly to the hindquarters of the giant birds to feed. The boomsinger, living on such a larger scale than its assailants, is virtually helpless to their attacks, enduring an onslaught of tiny ice cream scoops that bite at its flanks like a cow endures fly bites. Adult boomsingers invariably show many of the silver dollar-sized scars their sharp jaws leave in their wake, and though each nightbiter only needs one meal every two or three days, the sheer quantity of regenerating food that whole herds of such giant animals can provide can mean that the parasites can easily reach plague population levels where thousands may feed on a single animal, putting it at genuine risk of succumbing to infection of unhealed wounds - a very literal death by a thousand cuts.

But this is where the flapsnapper comes in. This larger tribbat predator holds no inhibitions against eating family, and it has become the primary limiting factor in the population of the nightbiter. A smaller tribbat that has just fed on a mouthful of bird flesh is extremely nourishing for itself, and so the predator becomes the prey. Flapsnappers are drawn to boomsinger herds in pursuit of gorged nightbiters, where they either snatch them right out of the air or land on the backs of the birds and suck them right off before they can disconnect their jaws and escape. Each flapsnapper can eat four or five nightbiters daily, and will do so every night if it can. They thus severely stress the parasites, limiting their populations and considerably reducing the time they spend biting their hosts, to the benefit of the boomsingers. Where flapsnappers are now found alongside nightbiters, they are kept at low enough populations that they do not cause enduring harm to their prey, and a balance occurs. In this way, this unusual food chain demonstrates the way that life ultimately finds a new equilibrium, adapting to check and balance changes to a formerly stable ecology, and eventually restoring that stability again.

Under Serina's twilit night on the savannahs of Serinarcta a pair of giant boomsingers wanders, flanked by comparatively tiny circuagodont grazers, as several flapsnappers circle around them to hunt nightbiters. Once finding limitless food with these giant prey, today the nightbiter is itself heavily preyed upon and forced to maintain a low profile as the unwitting base of its own food chain.

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The final tribbat group that we will cover today is the most derived of all. While less physically strange perhaps than the moonbeast or the nightbiter, it is the vibropterans that are the most unusual of all divopterans... for they alone have forgone hunting almost entirely, trading flesh for the nectar of flowers, fruit, and the tiniest of flying insects. With 320 species, they are the most specious and currently the most rapidly evolving subclade of all tribbats in the early Ultimocene. Vibropterans are the best flyers of all tribbats, with small bodies and narrow wings that flap rapidly and allow hovering, and they are the group that is currently most competitive with birds, particularly the smaller sparrowgulls, whose niches they readily take over and who have no vulnerable eggs to protect from molodont egg-eating predators, for as with all tribbats they give live birth. Their flight is more energetically efficient than a birds, and they have one major advantage over many nectar-drinking birds particularly in cold climates; many can lower their body temperatures, slow their breathing, and hibernate through winter, thus avoiding migration. This is something that among other pollinating birds only the semi-carnivorous switchbeaks, a clade of metamorphic birds, can also manage.

Vibropterans range in size from about an ounce - the size of a sparrow - down to two-tenths of an ounce; around the weight of a hummingbird. They may be small, but it is these among all tribbats who are the pinnacle of their long evolutionary history toward nimble flight, and subsequently which may ultimately go on to the biggest things.

Smaller than a human thumb, the blue-eared vibropteryx is among the smallest of all tribbetheres. A nectar-drinking specialist, it uses a long brush-tipped tongue to gather its food, which is supplemented with insects.

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These tiny nectivorous tribbats move through the air effortlessly, zooming up, down, and side to side with their wings fluttering through a full stroke up to fifty times a second. They come in brilliant colors, with new species evolving in a matter of just a few thousand years rather than millions, and each species marked boldly in its own distinctive color pallet. Golden, orange, red, black and white hair overlies blue, green or red skin that combines to create every color possible, often many in a single animal. Though they descend from carnivores that in turn became insectivores, and indeed share a more distant relationship with the flapsnapper and the nightbiter, they only supplement their diets with tiny insects today and instead greatly prefer sugar-rich food sources. The tribbat analogue to hummingbirds on Earth, these little flyers are very distinct in at least one way; whereas hummingbirds are fiercely territorial, these little guys are extremely social.

Rich rainforests in central Serinarcta provide abundant blooms and berries, supporting flocks of these diminutive tribbats. By living in groups as they do, they must share all resources they find but this is outweighed by having the ability to maintain a far larger territory and defend it from rivals. When foraging, flocks flutter and fly from one sunlit flower patch to another, lingering for just a moment at each spot before moving on. They communicate with twitters and quiet hums, always maintaining awareness of where their companions are. Males and females flock together, females being promiscuous and every male getting an chance to mate, and all of the males assist in provisioning the young, reared in intricately woven nests of grass strung up from vines in bunches of three or four, and fed primarily insects before maturity. With numbers to back them, even these tiny tribbats can collectively defend their nests from predators, with some members of the flock often serving as a lure to turn their enemies' attentions away from their offspring.

With the largest brain to body ratio of all tribbats, vibropterans are highly intelligent. They have to be, for feeding on flowers requires remembering the location of every flowering plant in one's territory, but also the specific time - sometimes a span of only days - when it blooms, at one time of day, as well as when you've left fed there, for each flower only produces a small reward of nectar each meal and takes time to regenerate it. All of this information must be stored in their brains and forms a three-dimensional mental map of their environment containing the location of every single food source in their territory - which may be several acres horizontal and hundreds of feet vertical in the forest. And large brains allow for behavioral flexibility too, that can at times even subvert millions of years of evolution: birds and flowers, as well as flowers and insects, have established relationships going back countless millions of years, where plants and animals co-evolve to match - so that a certain birds' beak might match a certain flowers shape exactly. Vibropterans, clever creatures as they are, rapidly learn that if their tongues cannot reach down a flower to a pool of nectar, they can simply tear it apart with their wing claws to access the food within without pollinating it at all. Thus, as time goes on, these tiny nectivores which have already experienced such a rapid boom of physical diversity begin to shift toward increased behavioral complexity. And with many animals on Serina, once the ball towards complexity begins to roll, changes can accumulate quite quickly. To feed on a flower too big to reach with their tongues and too strong to tear with their claws, why not use a stick? By doing so, the vibropteran tribbats are thus the first tribbetheres to utilize tools. And they don't stop there; what other food sources might be accessible once you are not limited by your body to reach them? Other vibropterans learn to access the juicy interior of massive fruits, co-evolved with large herbivores who distribute the seeds inside and never meant for them, in the same way, and find food suddenly much more available - and easier to obtain - then if they relied on flowers alone.

The vibropterans - a clade of tiny, highly volant, intelligent, tool-using, social tribbats descended from large carnivores, prove that it is sometimes the most unusual forms can have the potential for great things. And in another timeline, they might rise to prominence. Yet not all creatures that have potential will get the chance, in a world changing quickly. Upcoming climate change will be disastrous to this small, tropical species, and its longterm prospects, like those of so many species, are dim.

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Serina in the early Ultimocene is approaching an end - but it must be remembered, all that has changed since the Pangeacene, so far, is an arbitrary title. Though volcanism has become unpredictable and continental drift is now slowing to a stop, life goes on and evolution has not slowed. Not everyone will make it, but some clades continue to spread far and wide, as life tries ever newer things and finds solutions to ancient problems in novel ways. This is true of the tribbats as much as any other clade, and they join ever more animal groups rising higher on the cognitive ladder. Developing slowly but surely, and piece by small piece, a more complex biosphere than has existed ever before is still forming as the Ultimocene goes on.