About 70,000 years ago in Africa, humans expanded into more extreme environments, a new study finds, setting the stage for our global migration. By Carl Zimmer Geography is one of the things that ...

Humans, when told not to communicate, tended to "pull toward the lowest common denominator, the greedy option, as would a newly attached ant," the authors wrote.

Ancient humans in Africa changed their behaviour in a major way 70,000 years ago, which could explain how their descendants managed to people the rest of the world ...