Begun believes that apes became extinct in Africa around 12 million years ago and that our earliest direct ancestors evolved in Europe, which is rich in ape fossils from 12 to 6 million years old. The book begins with a foreword by one of the earliest and most prominent objectors to the hypothesis, the University of Toronto professor David R. Scientifically rigorous and written with a clarity and candor that create a gripping tale, it presents a powerful challenge to proponents of the Out of Africa hypothesis. These objections had long been ignored, but now, in her splendid and important new book Ancient Bones, Madelaine Böhme and her collaborators Rüdiger Braun and Florian Breier have taken them up. If equivalent effort was put in elsewhere, skeptics argued, important finds might be made. And some worried that the Leakeys and others had found fossils only where they looked for them-in Africa. They pointed to a suspicious gap in the African fossil record between 12 and 6 million years ago, just when the human and chimpanzee lineages were diverging. Some researchers began elaborating an all-encompassing Out of Africa theory, which had three components: (1) our hominin lineage (which split from chimpanzees between 13 and 7 million years ago) arose in Africa (2) our genus, Homo, arose in Africa about 2.3 million years ago, and (3) our species originated in Africa about 300,000 years ago.īut there were always a few dissenters who, like Darwin, felt that the significance of fossilized fragments from Europe and Asia had been overlooked. When, beginning in the 1980s, genetic evidence suggested that our species ( Homo sapiens) originated in Africa, the case seemed settled: Huxley, rather than Darwin, had been right about our origins. It seemed as if these astonishing African fossils illustrated most of the important steps in the human evolutionary story. In 1984 a team led by Louis and Mary Leakey’s son Richard unearthed a skeleton of Homo erectus at Lake Turkana in northern Kenya that was 90 percent complete. Four years later Mary Leakey found 3.6-million-year-old hominin footprints at Laetoli, Tanzania, providing the earliest evidence of bipedalism. With a catchy name and providing powerful, easy-to-understand support for an African origin, Lucy soon became a household name. In 1974 an international team in Ethiopia led by the paleoanthropologist Donald Johanson unearthed the skeleton of the three-foot-tall bipedal ape Australopithecus afarensis, who became popularly known as Lucy. After that, the discoveries just kept coming. Homo habilis, or “Handy Man,” was a toolmaker hailed as the oldest “true” human ever discovered. With powerful teeth and a prominent crest atop his braincase to anchor prodigious chewing muscles, he was an archetypal “ape man.” I recall as a child staring awestruck at a painting of Paranthropus that combined the features of gorillas, chimps, and humans, and that powerfully cemented in my mind the idea that Africa had been humanity’s cradle.Ī few months after this discovery, the Leakeys made a second, even more significant find-a jaw attributable to an early member of our own genus. Paranthropus boisei, as it became known, belonged to a male upright ape who had stood around five feet high, weighed 110 pounds, and lived 1.8 million years ago. Then, in 1959, Mary discovered a fossilized skull that made headlines around the world. Amid the dust, sweat, and inconvenience of remote field camps, they simultaneously dug for fossils and raised three boys, often finding nothing of significance for years at a time. Louis and Mary Leakey began their search for fossils of human ancestors in Olduvai Gorge, in what is now Tanzania, in the 1930s. It was the pioneering and indefatigable Leakey family who found evidence for Huxley’s narrowly supported hypothesis. Aware of the discovery of fossils of apes in Europe dating to the Miocene Epoch (around 23 to 5 million years ago), he opined that “since so remote a period the Earth has certainly undergone many great revolutions, and there has been ample time for migration on the largest scale.” 1 (The latter had first been described by Europeans just sixteen years earlier, in 1847.) Darwin himself, however, demurred. Known as “Darwin’s bulldog” for his ferocious defense of Darwin’s evolutionary theory, he had been struck by the distribution in Africa of our nearest living relatives, the common chimpanzee and the gorilla. Huxley proposed an African origin for humanity.
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