Serinaustran Steppe

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The Serinaustran Steppe

Most of Serina's southern continent at the start of the Ultimocene (250 million year hence) is dominated by an enormous grassland that extends to the edge of the southern ice cap. The region is cool, the northernmost stretches reaching summer temperatures only in the seventies Fahrenheit and winter lows of thirty below zero occurring in the far south. It is also arid and receives very little rain for most of the year, instead obtaining most of its annual precipitation in the form of winter snowfall that irrigates the land through the spring and summer as melt water. This is nonetheless sufficient water for a healthy cover of low-growing vegetation to survive, which are relied upon by millions of large herbivores. The constant trampling and turning of the soil by the beaks and claws of the grazers destroy slow-growing mosses and bryophytes and stunt the growth of most woody plants, which means the steppe is dominated by hardier grasses, herbs, and patchy low-growing shrubs which can quickly recover from animal-inflicted damage. Long summer days provide plenty of energy, and the vegetation grows rapidly, making the most of the brief growing season.

Circuagodonts in particular thrive on these cool southern plains, migrating to the edge of the ice pack in the summer to feed on the lush melt-watered plains, and dozens of distinct species have evolved to survive here, each feeding in a distinct pattern and avoiding competing with their neighbors. Large horse-like species crop the older grasses down to the roots, while smaller antelope-sized species then feed on the tender regrowth that results. The large herds of herbivorous forms are pressed by pack-hunting carnivores, which keep their grazing relatives wary and on the move and prevent them from totally destroying any single patch of the grassland. In the fall, when the cold returns, most return to milder northern regions where the cold is less intense.

Giant archangels, some with fifty foot wingspans, fly south as soon as the snow melts to graze on the bountiful vegetation on the steppe, forming flocks thousands strong which darken the skies with their plane-sized silhouettes. Their deep, trumpeting calls echo from above and can be heard as far as five miles ahead of the traveling flocks. Some individuals make an annual round trip from the plains in northern Serinarcta to the southern steppe every year, fleeing the arrival of winter on both sides of the world and constantly chasing the summer. When they reach their destinations, they drift down in their flocks onto the plains with their wings spread out like hang gliders, scattering herds of circuagodonts in their wake. Herbivores initially fear them, but soon come to ignore them and even walk right between them, as the giants are docile and vegetarian. Once arrived, they spend the summer alternately courting and mating and eating around the clock, putting on weight to fuel them on their journey back up north in a couple of months at the return of autumn, at which time the fertilized females will stop to lay their eggs in the warm tropics. There are no pair bonds in the flying giants, and males and females are equally promiscuous, associating in large mixed-sex flocks on the ground that, once landed, will not take flight against until the autumn unless seriously pressed by predators.

Unlike the archangels, the grazing circuagodonts complete their reproductive cycle on the steppe and give birth to their calves in the spring, protecting them through the summer on the plains until they can feed themselves. Their parents are very defensive, but many young are still lost to the coordinated groups of predatory circuagodonts that trail the herds through the summer, as well as to attacks from the sky by large carnivorous birds - the archangels' less docile relatives - that swoop down and spear unsuspecting prey right off the grass in their long beaks. Large and antagonistic bumblebadgers known as bumblebears also skulk across the steppe, scavenging on the remains of other predators' kills, snatching up molodonts and birds' eggs and running off with any newborn calves it can snatch. Much larger than their ancestors in the Pangeacene, they have more specialized forearms to improve their efficiency. Though the arm, being in fact a hyptertrophied wrist, can still only rotate at the shoulder, the shoulder blades have become outwardly projected, resulting in a pillar-erect gate in the front legs that lets the bumblebear run surprisingly quickly in short bursts. The jaws have also further adapted, with the keratin teeth becoming larger and more prominent, in particular a highly enlarged pair of projections on the top and bottom which operate like canines, and the fleshy lips around the beak evolving further into cheeks around the back of the jaw which allow the predator to gnash its jaws and chew its food better before swallowing. Like the toothy beaks of circuagodonts, these projections take some time to develop in the young, and mothers exhibit a great deal of care toward their offspring, feeding them until they can do so themselves. Though they prefer a diet of animal prey, they also use their large claws to dig out roots and tubers and will also eat smaller quantities of berries, grasses and herbs.

The brief summertime boom of vegetation and grazing animals also provide plentiful food for insects, both vegetarian crickets - some of which take five summers to reach maturity - and blood-sucking flies, which in turn attract large flocks of insectivorous sparrowgulls.

In the winter, when the grasses dry up and powerful blizzards sweep over the steppe, all but the hardiest animals head north toward the forests, where many grazing circuagodonts change their diet to one of twigs and buds, taking advantage of the cold weather and the resulting dormancy of the ant trees' protective armies to feed freely until the insects re-emerge in the spring. Their predators, the carnivore circuagodonts and the bumblebear, follow suit. Almost all birds also pick up and leave, either on foot or on the wing - archangels head to warmer pastures, along with the predatory species which winter on the equatorial grasslands. Only the small burrowing molodonts stay the winter, stashing stores of grass seeds in underground burrows and then hibernating through the harshest months of the year. A few of the largest and hardiest grazers may also stay put in the northern reaches of the steppe, actively shoveling away the snow from the ground so they can continue to scrape out a living on the frozen vegetation.