The first fossil evidence of a brain of even vaguely human aspects dates back to eighteen million years to the Miocene Period, when an anthropoid ape which we call Proconsul or Dryopithecus appeared. Proconsul was quadrupedal and arboreal, probably ancestral to the present great apes and possibly to Homo sapiens as well. He is roughly what we might expect for a common ancestor of apes and men.
