Diversity of the Vivas

The Aardgeese, a group of ancestrally herbivorous flightless canaries which first appeared forty million years ago, have become one of Serina's most diverse groups on land. In the hundreds of thousands of thousands of generations since they first appeared, the group has exploded in diversity and spread across the planet, from east to west and pole to pole. Since the separation of Anciska and Striata in the north, however, different lineages of the clade have been isolated from one another. In the east, the Ovovivaves, a group of cursorial birds which practice internal incubation of their eggs, have spread and diversified abundantly. Different lineages have developed to exploit a wide variety of ecological niches in addition to herbivory, including carnivores and specialized insectivores, displacing many other canary groups, particularly early predator lineages.

In the increasingly isolated west, however, where the aardgeese first originated, a wider variety of unrelated canary diversity survives. The continents of Anciska and Striata separated shortly after the ancestors of the ovovivavian aardgeese crossed into the east, providing a haven for diversity which has been lost or is withering elsewhere in the face of competition from this up and rising new group.

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The Live-bearing Bird

Ovovivavian aardgeese - vivas, for short - are not truly live-bearing; rather, they lay eggs which hatch within hours, sometimes as long as a few days, of exiting the body. Nonetheless, this is such an advantage over the lengthy external incubation periods of other birds that by 50 million years PE the vivas have out-competed them to a very significant extent in both polar regions upon Serina's eastern supercontinent, where the cold climate makes traditional nesting difficult for large terrestrial birds. By the time such birds will have begun laying, the live-bearers will have already born their chicks. In addition to totally displacing other herbivorous groups, such as the blundering wombels, the vivas have begun to greatly diversify ecologically. One notable group remained herbivores, specializing further into their grazing or browsing niches and developing more efficient methods of feeding. Known as serilopes, they chew their food like the ancestral viva of 25 million years ago, using a muscular tongue to grind plant matter against plates in the roof of the mouth before swallowing, and in order to keep it in the mouth, they've now begun to develop fleshy cheeks along the mouth to prevent it from being lost before it gets to the stomach; the beak has become reduced to the end of the snout, fulfilling a niche like the front teeth of a mammal.

Other vivas became generalists, moving away from their initial browsing adaptations and adopting more carnivorous habits. Some, already consuming an occasional insect while foraging for plant food, begin to include these more frequently in their diets until they eat little else, others learn to break open and eat the eggs of more primitive birds and begin driving most of their former predators to extinction before moving into their niches themselves by feeding on first small, then larger animals. Mirroring the earlier predator canaries, the skykes, truly hypercarnivorous vivas evolve to pursue and hunt other flightless birds. Some specialize for speed and run down their meals, killing them with the beak like Earth's terror birds, while the elusive banshees specialize as cunning, solitary ambush hunters, leaping upon unsuspecting victims, digging in the claws, and flapping their remnant wings to keep balanced before delivering a killing blow with a powerful jaw in the manner of raptors.

One of the more novel niches which vivas have exploited on Serina by this time is that of giant, ground-based ant-eaters. Forest communities worldwide have appeared on the world now which are largely or entirely symbiotic with ants. Ants protect the trees from browsers and mow down competing vegetation and now are sometimes even necessary for the dispersal of the trees' seeds and their continued survival. As plant and ant have forged a link, the ant population has skyrocketed, and the bulk of animal mass in some Serinan forests is now made up mostly of trillions of these arboreal ants, making them a much more available food source than on Earth. Birds like the shimmersnoot, tropical jungle-dwellers with faces highly elongated and protected from stinging bites by hard, iridescent scales and scutes, may otherwise be shaped like browsers with long necks and long legs, but feed not on the leaves of the forests they skulk but rather the enormous quantities of ants that come rushing to the defense of the branches as it rustles through them. For most browsers the ants are a nuisance, but for the shimmersnoot, they're exactly what it's come for. Weighing several hundred pounds and standing taller than a man, it sweeps up more than twenty pounds of them from the canopy in a good day with its long, bristle-covered tongue, and still makes no noticeable dent in their numbers overall. The shimmersnoot's jaw is partially fused and the beak reduced to a small hooked covering on the tips of the jaws able to break open ants' nests within plant tissues to get at its prey.

Also insectivorous are the bumblets, very small aardgeese which have evolved to dig and shelter in burrows for protection from predators and inclement weather, using the very large claws on their alulas to loosen the soil ahead of them and kicking it behind them with their very large feet. They feed mainly on earthworms and the larvae of beetles and have a long, tweezer-like beak to snatch this prey up with but still grind it in the mouth before swallowing it. Though they are true vivas and incubate their eggs internally, they are quite divergent from their relatives. Most closely related to the shimmersnoots, they lack the specialization of them to feed on ants and have a much longer beak that covers most of their jaw, as in the ancestral canaries.

Vivas are the first bird group on Serina to truly re-develop a long tail, and most groups exhibit both an elongated torso behind the legs which supports the ovaries of females and additional vertebrate on the end of the spine. The tail helps the birds to maintain their balance, being at its extreme in species which frequently run at high speeds.

above: clockwise from left: red-crowned banshee, a dog-sized ambush predator. Jumping on the back of prey and holding on with the hooked talons, it kills it by biting into the neck with the powerful beak.

Imperial shimmersnoot, a large and long-legged ant-eater, the shimmersnoots are the only vivas to retain fully-developed plumage on their necks, which sport colorful iridescence. Such vaned plumage is also still present on the crowns, wings, and tails of most vivas, while the body plumage is extremely primitive and hair-like, made up only of single unbranched strands. Males use their colorful necks, as well as the vibrant scales on their long snouts which give them their common name, to entice potential mates.

Black-backed serilope, a gregarious herd-dweller from the cold northern plains, which exhibits a large and swollen covering to its nostrils useful for heating cold polar air before taking it into the body. The structure is filled with thick bristles and is also effective at filtering dust from the air.

Banded bumblet, a small burrowing insectivore, it has reduced wings but very large thumb claws used to dig large and often quite complex communal burrow systems.