During most of the Cenozoic the primates have enjoyed a degree of security among the treetops. For even though there were some predators, none was adapted to prey on them specifically, but that was before the striger.
This fierce little creature, developed about 30 million years ago and spread throughout the rainforests of Africa and Asia, its success hinging on the fact that it was as well adapted to life in the trees as its prey. The striger even adopted the bodily shape of the monkeys on which it fed; a long, slender body, forelimbs that could swing apart to an angle of 180 degrees, a prehensile tail and opposable fingers and toes that allowed it to grasp the branches.With the coming of the striger the other arboreal mammal fauna of the tropical forest underwent considerable change. Some of the slow-moving, leaf-and-fruit-eating animals were wiped out completely. Others, however, were able to adapt in the face of this new menace. As usual, when an environmental factor as radical as this is introduced, evolution takes place in a rapid leap, because now quite different physical attributes are advantageous.
The clatta, with its heavily armored tail protected by a series of overlapping horny plates, demonstrates this principle. When a striger attacks, it drops down and hangs from a branch by its tail. The clatta is now safe (the only part within reach of the predator is too heavily armored to be vulnerable).The khiffah defends itself with skill, thanks to adult males having a unique set of features to carry out their highly specialized role in protecting their colony's citadel; horny armor over the face and chest and vicious claws on the thumb and forefinger. It is not unknown for a female to taunt a passing striger and allow herself to be pursued back to the citadel, dashing to safety while the striger finds its way barred by a powerful male capable of disemboweling it with a swipe from its terrible claws. This apparently senseless behavior, however, provides the colony with fresh meat, a welcome supplement to their basic vegetarian diet of roots and berries. Only young and inexperienced strigers are caught this way.