This chapter applies evolutionary concepts to the understanding of human origins and explains the biological variation seen in our ancestors across time. Chapters 4, Biological Evolution and Early Human Evidence and Chapter 5, The Genus Homo and the Emergence of Us, represent a field of study that is probably the most dynamic, controversial and highly debated subfield of anthropology. Perspectives and opinions vary not only within the mindset of the general public but also amongst scientists and anthropologists alike. As the human fossil puzzle begins to fill in with new discoveries, we find ourselves gaining valuable insights into what makes us human and the ways in which we are a part of, not separate from, the natural world. Despite our advances in the field, we also have to be prepared for the possibility we may end up with more questions than answers! It is these very reasons that explain why so many of us find this such a fascinating field and why so many of us take it so personally. It is after all a journey into the discovery of who we are and where we came from; and that should be of interest to all of us as members of the Homo genus.