In this series, James Kidder provides an intriguing study on transitional fossils and the evolutionary history of modern humans. He begins by discussing the fossil record, explaining how new forms are classified. He then explains the physically distinguishing trait of humankind—bipedalism. From the discovery of Ardipithecus, the earliest known hominin, to the australopithecines, the most prolific hominin, Kidder focuses on the discovery, the anatomy, and the interpretation of these ancestral remains.

This BioLogos videocast addresses the age of recently discovered hominid fossils and how scientists are able to obtain those dates.

In recent decades, scientists have discovered more about the beginnings of humanity. The fossil record shows a gradual transition over 5 million years ago from chimpanzee-size creatures to hominids with larger brains who walked on two legs. Later hominids used fire and stone tools and had brains as large as modern humans. Fossils of homo sapiens in east Africa date back nearly 200,000 years. Humans developed hearths for fire, stone points for spears and arrows, and cave paintings by 30,000 years ago. By 10,000 years ago, humans had spread throughout the globe. Genetic studies support the same picture. Humans share more DNA with chimpanzees than with any other animal, suggesting that humans and chimps share a relatively recent common ancestor. Also, the same defective genes appear in both humans and chimps, at the same locations in the genome—an observation difficult to explain except by common ancestry. Genetics also tells us that the human population today descended from more than two people. Evolution happens not to individuals but to populations, and the amount of genetic diversity in the gene pool today suggests that the human population was never smaller than several thousand individuals. Yet all humans, of all races, are descended from this group. Humanity is one family.