A veteran anthropologist writes a superb overview of how our species developed (a long process) and how we grew smart enough to dominate the planet (a short process in which evolution played little part).
Tattersall (Paleontology: A Brief History of Life, 2010, etc.), curator emeritus at the American Museum of Natural History, begins with early hominids, who took the first step away from apedom about 5 million years ago by rising to walk on two legs. In absorbing detail, he describes two centuries of often-grueling field research that turned up more species that learned to make tools and whose brains slowly grew. For 3 million years, our small-brained ancestors, the Australopithecus genus, spread throughout Africa before leaving the scene. From about 2 million years ago, bigger-brained members of genus Homo ranged across Eurasia without making a great impression. Homo sapiens, remarkably young at 200,000 years, did not seem a great improvement until about 60,000 years ago, when their brains began processing information symbolically, leading to language, art, technology and sophisticated social organization, all of which accompanied our species across the world, wiping out competing hominids. While researchers argue over why this happened, Tattersall emphasizes that evolutionary milestones, even dramatic ones like flying, do not happen when new features appear but take advantage of those already present. Feathers existed long before birds flew, and Homo sapiens’ brains were always capable of great things.
Keeping a critical eye on the evidence and a skeptical one on theories, Tattersall confirms his status among world anthropologists by delivering a superior popular explanation of human origins.