“When a species of primate, homo sapiens, became much smarter than other primates, it pushed all the other ones into a very small habitat. So there are very few mountain gorillas and orangutans and chimpanzees - monkeys in general. They occupy small corners of the world - cages...zoos. Even the jungles that they're in are narrowly defined so they were sort of like big cages ... So, you know, that's one possible outcome for us.”

Source: Wikiquote