Clatta

The clatta, Testudicaudatus tardus, is a gray, herbivorous, lemur/sloth-like loris from the tropical forests of Asia, from After Man: A Zoology of the Future.

It is a prosimian with a heavily armored tail protected by a series of overlapping horny plates, demonstrating the principle of tree-dwelling primates that devloped new physical attributes to protect themselves from strigers. Before the arrival of the advanced tree-living predators, such a tail would have been a disadvantage, interfering with the efficiency of food gathering. Any tendency for such a cumbersome structure to evolve would have been quashed rapidly by natural selection. But faced with constant danger the efficiency of food gathering would have taken on an importance secondary to defense and would have therefore created the correct conditions for it to evolve.

The animal itself is a leaf-eater and moves slowly, upside down, along the boughs. 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).