Watertrotter

In the south there has evolved a foxtrotter species that in many ways mirrors a counterpart found in the north despite having diverged from one another ten million years ago. In an example of convergent evolution both the Serinarctan triyenas and the Serinaustran watertrotter have specialized to catch fish in freshwater habitats, developing greatly elongated jaws with many hooked teeth, and even a small notch in the upper jaw to help hold slippery prey in place. Yet these adaptations arose in each group wholly independent of the other, and they are no closer related than either is to any other foxtrotter from the other hemisphere. Similar environmental conditions - namely, very wet, flooded landscapes - have produced some similar traits in both animals. But the differences are significant, too. 

While both the contemporary finfoot triyena and watertrotters have long jaws to catch fish, they differ markedly in the way they go about it. The triyena is more specialized, with lobed digits that make it an effective swimmer, and hooked claws to grapple with big aquatic animals. The watertrotter more closely resembles the behavior of the earlier fishing triyena, being a wader that pounces on fish from shore, though it is smaller and more delicately built. Descended from the white-tipped brushtrotter, watertrotters still have some arboreal capacity, and can use their long fingers and muscular arms to climb trees to rest or avoid larger and more dangerous animals. They are similar in some ways to a heron-like raccoon, while the triyena is more akin to an otter-like bear. Both body forms are well-suited to catch different types of fish, with the triyenas able to wrestle much larger food sources but the watertrotter being much more adaptable in its diet and able to subsist on prey that would be too small for its counterpart in the north.

The nocturnal watertrotter prefers to feed in darkness, when fish are less wary and the world is quieter, letting it more quickly sense the approach of threats with its large ears and keen eyesight. It typically lives in pairs which cooperatively rear their pups, and dens in hollow trees or riverbank burrows dug out by other animals. The young are nest-bound until about three weeks old, guarded at all times by the mother while the male is expected to deliver food to feed the entire family. When they are strong enough to hold their parent's fur in their hands and cling to their backs, they will leave the den to hunt with them during the night. Fishing is not dangerous, and so as in the finfoot triyena the young can join their parents and begin to learn the techniques as soon as they are physically capable of trying them. To get them interested in catching their own food their parents begin crippling small fish so they cannot easily escape and placing them in very shallow water for the pups to play with, gradually working up to larger, healthy fish that are dropped in isolated pools so they can dash around the water and be a challenge to catch, but not escape back into the river away from the young. Watertrotters can also feed on land animals such as birds and even, rarely, smaller foxtrotters - including closely related lemur-like scamps, which share a close ancestry with the brushtrotter lineage. To catch them, it may utilize simple tools - sharp sticks - to skewer them from the tree holes they hide in. Such food makes up only about 10% of the total diet though, which is 80% fish and aquatic life. The last 10% is mostly comprised of fruit, a sweet treat that these animals sometimes enjoy when they come across it, having not yet lost the ability to taste sugars as many obligate carnivores eventually do.

Watertrotters rarely use tools when hunting fish, even though they are intelligent enough to learn to do so to catch arboreal prey that is otherwise hard to get, perhaps because they are already so well specialized to hunt in water with their own teeth and claws that tool use is superfluous. They do, however, make use of rocks to bust open the shells of molluscs too strong for their jaws to crack and some populations specialize in this as their primary way of collecting food, teaching the trick to their young. Ancient smashing stones, often some distance from water, accumulate piles of discarded shells around them from generations of watertrotters using them to crack open a meal. The same stones, and indeed the techniques in general, are shared by some other animals in the watertrotter's range, especially scroungers, some types of trunkos, and sparrowgulls that all also enjoy shellfish. Which of these many species developed such a knack for tool use first is hard to say - all these groups are intelligent, social learners, and can acquire knowledge culturally beyond their own species by watching other types of animals perform the action. This capacity, which is only now in the late Ultimocene becoming commonplace in Serina's wildlife, leaves many opportunities for inter-species interaction beyond the ancient predator and prey dynamics. Watertrotters have varied and complex interactions with other animal species, and young animals often play together while adults share the same space and learn foraging techniques from each other. This phenomenon of amicable social interaction is not limited to the southern biopshere, but is becoming more and more common all across the world - likely a direct result of the opposing force seen in other animals like thorngrazers and gantuans, to be highly aggressive, strong, and independent at the expense of brains. In a world of bigger and more belligerent rivals like these, it pays to form alliances with other creatures that are able to think before they fight.