At what point did humans begin to develop distinctive physical traits as a result of their geographical location? I.e. At what point did races start to develop and how?

by SHbhar
Searocksandtrees

Hi, for questions on early humans, it would be worth x-posting to our sister sub /r/AskAnthropology. While there are some anthropologists here, there are more there, and with a greater specialization in pre-history