Ans: New species form when a population becomes isolated and undergoes genetic change through mutation or genetic drift; eventually enough changes have accumulated so that the new species is no longer sexually compatible with the old species. Speciation is prevented if gene flow continues between populations.

Ans: Yes, humans share many similarities with primates, because humans are primates. While there are some key traits that are unique to humans, like kinship, there are a series of important similarities that we share with non-human primates. Interestingly, many of these traits were once thought to be found only in humans, but as our understanding improves, it has become clear that we share many behaviors with non-human primates. For example, the capacity for learning, the deliberate manufacture and use of tools, hunting, and inter-community aggression were all once thought to be uniquely human, but now have been observed in different non-human primate communities.

Ans: Researchers comparing the mitochondrial DNA of several modern humans concluded that in order to produce the diversity present, all humans would have to share a common ancestor that lived approximately 200,000 years ago. They dubbed this hypothetical person "Eve." However, it is important to note that these researchers' "Eve" was a hypothetical, not an actual identified individual.