From the earliest days of their science, paleoanthropologists have shown a propensity to envision the human family tree” as a straight-line progression from the apelike australopithecines to the enigmatic Homo habilis to the perhaps misapprehended Homo erectus to the famous (or infamous) Neanderthals, culminating in us, Homo sapiens. The problem is that this model is unlike the evolutionary pattern of any other known vertebrate (or any organism, for that matter) which reveals multiple branching and extinctions.Since mid-century it has been evident that in South Africa two species of australopithecines existed at the same time, one of which a specialized vegetarian went extinct, leaving no successors. Then fossils were unearthed that demonstrated early members of our genus (Homo) existed side by side with australopithecines, complicating the picture still further. Now it is becoming increasingly clear that the Neanderthals were not a direct ancestor to modern humans but were in fact a side branch whose extirpation was at least partially at the hands of our modern human ancestors who invaded Europe 40,000 years ago. And very recent re-dating of several Javanese Homo erectus fossils has cast doubt on the notion that this widespread population was our direct ancestor.In Extinct Humans, Ian Tattersall and Jeffrey Schwartz present convincing evidence that over fifteen different species of humans have existed over the six million-year sojourn of the hominid family, and that many of these species have existed simultaneously. Furthermore, a large number of these were members of our own genus. Who were these different human species? What did they look like? When and where did they evolve? Which are direct ancestors to us and which went extinct, leaving no successors? And, the most profound question of all, why is there only a single human species alive on Earth now? Tattersall and Schwartz explore these questions and many more in Extinct Humans.
It's time for a hominid family reunion, and anthropologists Ian Tattersall and Jeffrey Schwartz have brought the scrapbook.
Extinct Humans is both an album of knowledge of our ancestors and closely related species and a theoretical reconsideration of the fossil evidence. Tattersall and Schwartz suggest that many more human species existed than we previously thought, and that many of them existed contemporaneously until about 25,000 years ago. Profusely illustrated, the book makes its case well, showing and discussing the evidence and proposing a family history that pulls all the fossils and theories together into a testable whole. The authors have personally investigated every available hominid specimen, and the depth of their knowledge is staggering at times--but their obsession is enlightening and entertaining.
The introductory history of human taxonomy sets us up for the discussions to follow and reminds us of our tendency to read more into human history than can reasonably be inferred from the evidence. The racist sentiments of 19th-century anthropologists found firm footing in their theories, and we can only wonder what mistakes we're making today. Doing their best to eliminate extraneous details, Tattersall and Schwartz provide a lean, parsimonious theory to guide anthropology into the 21st century, as we try to learn why we're the only ones left. --Rob Lightner
