Seven skulls vividly convey the long road of human evolution. From left they are: Adapis (50 million years ago), Proconsul (23-15 million years), Australopithecus africanus (3 million years), Homo habilis (2 million years), Homo erectus (1 million years), early Homo sapiens (92,000 years) and Cro-Magnon (20,000 years ago).