Swedish geneticist Svante Paabo is rewriting the story of human evolution. From 1856, when the first Neanderthal skeleton was discovered in the Neander Valley in Germany, to the dawn of the 21st century, the map of our origins had to be pieced together entirely from fossils. All this changed with the coming of rapid DNA sequencing and the Human Genome Project.
Paabo realised that if DNA could be recovered from Neanderthals (who became extinct about 30,000 years ago) and other early human ancestors, comparing the DNA of the genome with modern humans and great apes would increase the number of deductions that could be made concerning human evolution.
In 1991, a well-preserved body was disgorged by a glacier in the Tyrol. Otzi was 5,300 years old and Paabo honed his technique of amplifying small pieces of DNA to make them readable on this find. He then turned to Neanderthal man: the first DNA sequences were published in 1997, but it took another 13 years of work before the full Neanderthal genome, based on three individuals, was published in May 2010.
The science of human evolution has been dogged by two opposing dogmas: the "Out of Africa" and the "multiregional" hypotheses. The dominant Out of Africa theory claims modern humans originated in Africa about 200,000 years ago, and entered Europe, Asia and Polynesia 50,000 to 60,000 years ago, by which time all other forms of proto-humans (hominins) were extinct or about to become so. It is known that the first hominin to leave Africa, Homo erectus, reached China 1.8 million years ago, so the multiregionalists believe various groups of hominins coexisted from this time on.
Paabo has shown there was interbreeding between, at the present count, four distinct lines of hominin. So a hybrid of the two theories is now plausible: essentially Out of Africa but with complicated interactions thereafter.
Among other things, his book is fascinating for showing just how modern research teams work together and, sometimes, fall out.
Guardian News & Media