The Slashdasher and the Double Agent

Though the hothouse age has shown that high intelligence among animals is not absolutely necessary to be successful, long-held trends in evolution over Serina's history toward more behavioral complexity still remain among many lineages. Cooperative behavior, between different species, is as common in the late Ultimocene as before it, and such partnerships come in many forms.

The slashdasher is a small spire forest predator descended from the viridescent sawjaw, which has become especially nimble and quick. These animals have moved off the soglands and into drier upland habitats, where they now hunt prey that hides within clusters of cementrees to avoid larger threats. The slashdasher's thin form lets it follow animals like spiresprinters into cover, while its long legs and small feet aid it in running just as quick as its quarry over the drier ground. Though they have some vague resemblance to felines, as do many smaller sawjaws, the slashdasher actually demonstrates convergent evolution to canines as a pursuit predator with more reliance on the mouth and less on their claws to hunt. The highest dewclaw is now vestigial, and the lower one is also reduced in size, reflecting increased cursoriality versus earlier sawjaws. To compensate for less dexterity in their talons, slashdashers have an especially vicious bite; their teeth show sharp cusps not only on their inner surfaces but also irregularly on their outer ones as well. These additional sharp edges provide a more violent bite, as they slice flesh not only when the jaws are closed but again when they are opened. This is used by this species of sawjaw to inflict upon its targets the most damaging bites possible. Slashdashers don't have a quick or specific method of killing their prey species, instead snapping brutally at their hindquarters with their teeth until they are weakened enough to bring down. Unless the prey is very dangerous, they will begin to eat, usually from the wounds opened up on its backside, while it is still alive. 

These sawjaws are social predators and cooperate in groups to single out and bring down a target. In addition to spiresprinters, smaller, quick-running trunkos are the next most common food taken. The slashdasher is able to turn on a dime and accelerate very fast by using its long tail as both a rudder and an additional limb to hit against the ground for a burst of speed, yet it still must coordinate its attacks very well in order to outmaneuver and catch its equally agile targets. In the thickets of the spire forest, each individual is often unable to see the others it must work with to accomplish this goal. Loud vocalizations would frighten the animals they want to hunt, meaning the slashdasher has had to come up with a novel and intelligent solution to these problems - a way to talk to each other without being overheard. They do this through an alliance with a second animal species which is not viewed as a threat by any of their prey. The double agent is a small magpie-sized sparrowgull bird with a long, curved bill, which is native to the spire forest and adjacent grasslands. Much of the time, it is not only viewed as harmless by larger herbivore species, but beneficial, for it actively removes arthropod parasites off the skin of many animal species. But true to its name, this bird leads a double life.

Very intelligent, and always watching other animals around it for a chance at any sort of meal, double agents are also eager scavengers of predator's kills. They have learned that whenever slashdashers hunt, there is a great surplus of food to be found that is far easier to get than little bugs collected one at a time. Over time, simple kleptoparasitism has become something more complex, as the sawjaws, too, learned to take advantage of the double agent's level of trust with the herd animals. Now, when a pack of these predators is ready to go on the hunt, they call in the pickbird with a crude imitation of its high-pitched, whistle-like chirps. The birds, which themselves live in social groups, have come to understand this cue, and they go ahead of the pack and scout out the location of prey. Not viewed as a threat, they are ignored as they flutter through the forest, calling out the location of a suitable target. Individual birds fly back to individual sawjaws and lead them into positions they have chosen, effectively stationing each member of the pack around the prey in a big circle, so the fastest ones can most effectively chase it into a trap where several others, which are largest and most powerful, are posted in wait to catch it.  In this way, a flock of double agents coordinate the sawjaws - which remain silent and do simply as they are told - so that they do not need to do it themselves. For the sawjaws, this is a case of symbiosis with a partner, yet for the pickbird, it comes across more like the innovative use of the slashdasher as a tool. However the animals view their relationship, what really matters is that by working with the birds to communicate in ways that are not detectable by their targets, these sawjaws can have a higher rate of hunting success for a small cost - the little birds that make it possible only take a small portion of the kill for themselves, which is insignificant to the hunters. Prey animals never realize the double agent is dangerous because they never see it attack them, and the sawjaws can keep quiet when being guided in this way, so that they are much less likely to be detected until it's too late.

Double agents live in cohesive flocks with a dominant breeding pair and numerous helpers; this wolf-like social structure is ancestral to chatterravens. Nesting occurs in hollows in cementrees, or rarely in other trees or holes dug out in steep riverbanks and all adults in a flock provide care to the leaders' chicks. Young spend as long as three years in their natal group before dispersing. Double agents always forage in a group and don't frequently split up; there is safety in numbers. They utilize a wide range of vocalizations in different contexts; their normal communication calls are loud, shrill and bell-like, and these are used when foraging independently or cleaning insects from larger animals. When organizing a hunt, however, they switch over to calls that are fairly quiet, whistle-like and simplistic - they blend into background noises among other birds and insects, and so don't catch the attention of the animals they want the sawjaws to catch for them. These vocalizations are learned, not innate, and some populations of this species exist which haven't learned to cooperate with carnivores, and have only loud calls as a result.

Double agents are tight with their flocks and not willing to accept unrelated members into established groups - they drive interlopers away and may kill them if they don't make a quick retreat. Yet when young individuals leave their flocks, they may spend as long as a year in loose, non-territorial adolescent groups where they form their enduring pair bonds. Birds from cultures that only feed on small insects, and those from cultures which actively orchestrate hunts with sawjaws, can pair together, in which case the former adopts the additional quiet dialect from its mate over time - it is in this way that this cultural behavior has spread over Serinarcta.