Environment & Human Evolution

The fact that adaptive evolution may well depend on the individuals changing themselves and not just on environmental change, is especially important in human evolution, because there is an extra source of change: culture.

Cultural changes changed the relation of the hominins with their environment, changing the selective regime.

This, and not environmental change, may well account for the many things that have happened in human evolution

The fact that there were many shifts in temperature&precipitation, as well as a slight trend (decline) in temperature, during the last 7 million years doesn't quite add up to an explanation of, say, the steady increase in brain-size in human evolution.
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