, the biological and cultural development of the species Homo sapiens, or human beings. A large number of fossil bones and teeth have been found at various places throughout Africa, Europe, and Asia. Tools of stone, bone, and wood, as well as fire hearths, campsites, and burials, also have been discovered and excavated. As a result of these discoveries, a picture of human evolution during the past 4 to 5 million years has emerged. Human Physical Traits Humans are classified in the mammalian order Primates; within this order, humans, along wit ....