Regardless of the challenges involved in measuring the exact contribution of genes and environment, what is not debated is that humans, like all organisms, are the result of their interplay. In order to understands how people beings have evolved as somehow different from all other members of the living world, we need to examine ourselves within the larger context of that world, and particularly as members of a group of our closest relatives, the apes, monkeys, and chimpanzees whom we also call primates. Our place cannot be really properly understood unless we have an appreciation of exactly how we relate to these other members of the primates order: what we share, both in terms of genes and behaviors, and what makes us all unique. We will examine this aspect of our evolutionary history first, and then return to look in more detail at the environment.