There are four genetically distinct chimpanzee populations, all found in two relatively small regions of Africa. And yet these populations, which are sometimes less than a mile apart, are more genetically diverse than humans that live on different continents.
If man evolved in Africa, where did man's best friend come from? Scientists thought the first dogs came from the Middle East, but a new study of dog genetics suggests they actually come from one small region of modern China.
Survival of the fittest is, at its heart, an expression of the idea that natural selection will favor those species that are best adapted to their environment. But there might also be a place for the unfit after all.