Americopithecus

Americopithecus was a species of very large terrestrial baboon-like relatives of capuchin monkeys. It was probably as terrestrial as today's baboons and some macaque species. Its native habitats were most likely grasslands with trees. It lived from 4 million years ago to about as recent as 30,000 years ago. The reason for its extinction is unknown, but it is possible that the newly arriving baboons that arrived from Asia outcompeted them to extinction.