You also have to consider the time it took to reach Buttrumpet's distribution plan.

(I'm just reading about this, so it's right in front of me.)

Our origins in Africa as great apes: 7 million BC.

South-central Asia: by 1 million BC.

Europe: by 500,000 BC.

Australia: 40,000 BC.

Northeastern Europe (Siberia, etc.): by 20,000 BC.

Alaska into Canada: by 12,000 BC.

North America: by 11,000 BC.

South America (present Argentina): by 10,000 BC.

Greenland: by 2,000 BC.

Polynesia (including Hawaii): by 500 AD.


So it's not like this happens overnight.