Eosimias and the origin of monkeys
A primate the size of a mouse, found in China, moves the root of our own branch to Asia.
- When
- —
- Duration
- 5 million years
- Known to
- ± 2 million years
- Era
- Eocene, Cenozoic
Eosimias weighs perhaps 100 grams and would fit in a spoon, but its teeth and jaw carry anthropoid features — the traits that unite monkeys, apes and humans. Its discovery in the middle Eocene of China, along with related eosimiids and later ankle and finger bones, pushed the origin of anthropoids millions of years earlier than expected and shifted the likely place of origin from Africa to Asia, with a subsequent dispersal into Africa. The Africa-versus-Asia question is not fully closed, but the Asian case is now the stronger one.