Birds of prey such as eagles and hawks are the important predators of the treetops, as they are in any other habitat. The tree-living mammals of these regions must be swift enough to elude them and also to escape from tree-climbing predators coming up from below. The mammals that accomplish this best are the primates. The long-armed ziddah has taken these specializations to the extreme, and has developed long arms and legs, fingers and toes, so that it can brachiate, or swing, its tiny globular body through the branches of the trees at high speed. It has also evolved a prehensile tail, just as its South American cousins (the now extinct New World monkeys) did in the first half of the Cenozoic. Its tail, however, is not used for locomotion but only for hanging from when resting or asleep.