by JOHN NOBLE WILFORD
A conversation with Chris Stringer
Who are we, and where did we come from? Scientists studying the origin of modern humans, Homo sapiens, keep reaching deeper in time to answer those questions — toward the last common ancestor of great apes and humans, then forward to the emergence of people more and more like us in body and behavior.
Their research is advancing on three fronts. Fossils of skulls and bones expose anatomical changes. Genetics reveals the timing and place of the Eve of modern humans.
And archaeology turns up ancient artifacts reflecting abstract and creative thought, and a growing self-awareness. Just last month, researchers made the startling announcement that Stone Age paintings in Spanish caves were much older than previously thought, from a time when Neanderthals were still alive.
To help make sense of this cascade of new information, a leading authority on modern human evolution — the British paleoanthropologist Chris Stringer — recently sat for an interview in New York that ranged across many recent developments: the evidence of interbreeding between Neanderthals and Homo sapiens; the puzzling extinct species of little people nicknamed the hobbits; and the implications of a girl’s 40,000-year-old pinkie finger found in a Siberian cave.
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Speaking of DNA, what about the African Eve? This established an approximate date for the genetic origin of modern humans, in Africa. As a leading advocate of the recent African origin, in contrast to the multiregional model, did you believe this settled the debate?
To be honest, it’s not been totally resolved, but the Mitochondrial Eve publication of 1987 was a key moment. Up to then, a few of us were arguing for a recent African origin from the fossil and archaeological evidence. But the evidence was pretty skimpy, and the majority opinion was against our view.
When this new genetic technique appeared, it seemed to give clarity to the picture. Here was an independent bit of data, from our mitochondrial DNA, inherited through females, suggesting we originated, all of us, all over the world, from a single ancestral population that lived in Africa maybe 200,000 years ago.
I came to this conclusion gradually, starting with the Neanderthals. They were the best-known ancient humans, and there was a view that they were our ancestors. I tested that model in my Ph.D. research, and I concluded the Neanderthals did not make good ancestors of modern humans, even in Europe, where we had the best data. So gradually my search moved from one region to another, to see where the evidence best fitted the idea of our origins.
It turned out that Africa was the place that had the oldest fossils of modern humans. Africa, for me, was the only place that showed a transition from archaic to modern humans.
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