human prehistory: prologue
A Chimps Distant Cousin
You and your distant cousin, the chimpanzee, share a common ancestor who lived about 6.5 million years ago. Though we share many similarities, there are a few critical differences — such as upright walking and the capacity for abstract reasoning — that have played a crucial role in human evolution.
The Pre-Human Parade
The fossil record reveals a long and eventful parade of human ancestors. Gradually they became more efficient upright walkers and later developed skulls with larger braincases that were devoted more to thinking and less to chewing. Our knowledge of the exact relationships between these ancestors is incomplete, and often is revised because of new fossil finds.
The First Homo sapiens
Starting about 200,000 years ago, the fossil record reveals the skeletons of people who looked a lot like us. They were not exactly the same; they had sturdier bones and thicker brows than we do, but were similar enough to present-day humans to be considered members of our species, Homo sapiens. These early humans were strong and primarily depended on their muscles rather than technology for survival. But they had bigger brains than earlier hominids; they also built fires and flaked stone into spearheads, knives, and scrapers.
Filling in the Blanks with DNA
In addition to fossils, we have genetics to help us find our prehistoric kin. All of us living today inherited our DNA from a small group of ancient people. Scientists can study the DNA of living people to piece together information about who our earliest ancestors were, where they lived and how they gave rise to the diverse populations we see around the globe today.
Distant Cousins in Far Off Lands
Homo sapiens was not the only hominid alive during this time. Some of our cousins had been living outside Africa for hundreds of thousands of years. As a result of previous migrations, Homo erectus was living across Asia. Homo erectus had a big brain, some used hand axes, some built fires and some may even have worn clothing. At the same time, Neanderthals lived across Europe and western and central Asia. They had even bigger brains, made spears and stone tools similar to those found in Africa, and had strong social relationships. They cared for their sick and infirm, and buried their dead; not so very different, culturally, from early Homo sapiens.