The Human Chimp

Aug 22nd

How Similar are Chimps and Humans?

• Implications

• What are the similarities?

Molecular Clocks

• Used to measure genetic distances and to date times of evolutionary divergence

• How it works:

DNA• The best molecule for use with molecular

clocks• To measure the change in DNA structure:

– Mix DNA from 2 species– Measure how many degrees of temperature the

melting point of the mixed DNA is reduced below the melting point of pure DNA from a single species

– A melting point lowered by 1°C means the DNAs of the 2 species differ by roughly 1%

Family Tree of the Higher Primates

Man the Hunter

• Unclear whether early Homo sapiens were hunters or scavengers

• Big-game hunting led to…

The Human Family Tree

The Great Leap Forward

• When modern humans replaced Neanderthals• 3 changes launched us in the direction of

modern humans– 4 mya – upright posture– 3 mya – Australopithecus robustus and A.

africanus– 2.5 mya – tool use

• 40,000 years ago in EuropeThe Great Leap Forward

Examples of Aurignacian Culture art