The southward advance of native African farmers with Central African crops halted in Natal, beyond which Central African crops couldn't grow - with enormous consequences for the recent history of South Africa.

History followed different courses for different peoples because of differences among peoples' environments, not because of biological differences among peoples themselves

Australia is the most isolated continent.

The survival rate of Dr Burton's patients approximately doubled the maximum survival rate of conventionally treated patients. Had these findings pertained to a chemotherapy drug instead of IAT, massive amounts of funding would have been allocated to investigate the drug. Once again, the politics of cancer barred a potentially valuable treatment from reaching the public.

African cavalry mounted on rhinos or hippos would have made mincemeat of European cavalry mounted on horses. But it couldnt happen.

Although native Africans domesticated some plants in the Sahel and in Ethiopia and in tropical West Africa, they acquired valuable domestic animals only later, from the north.

No government is here forever. And there are other forces - the most potent force in our society, in fact, big business - doing good for the environment.