They were not quite hunter-gatherers besides hunting and foraging, they also practised slash-and-burn agriculture but they did live in self-sufficient villages, and there was little disparity of income between villagers.

ECONOMIST: Your parents were right. Patience is a virtue

Of the four global regions inhabited by primates, the worst hit is Madagascar, where loss of habitat to traditional slash-and-burn agriculture has left some lemur species, such as Perrier's sifaka, stranded in tiny areas of forest.

BBC: NEWS | Science/Nature | Quarter of primates face abyss