7/19/2023 0 Comments Smiling chimpanzee drawing![]() “I want to know what changed in fully modern humans, compared with Neanderthals, that made a difference,” he said. Pääbo already has a team scanning the two genomes, drawing up lists of likely candidates. Somewhere among the genetic disparities must lie the mutation or, more probably, mutations that define us. Neanderthals were very closely related to modern humans-so closely that we shared our prehistoric beds with them-and yet clearly they were not humans. At that point, Pääbo believes, an answer to the age-old question will finally be at hand. Once the Neanderthal genome is complete, scientists will be able to lay it gene by gene-indeed, base by base-against the human, and see where they diverge. The project is about halfway complete and has already yielded some unsettling results, including the news, announced by Pääbo last year, that modern humans, before doing in the Neanderthals, must have interbred with them. ![]() Pääbo’s most ambitious project to date, which he has assembled an international consortium to assist him with, is an attempt to sequence the entire genome of the Neanderthal. ![]() “The challenge is to address the questions that are answerable,” he told me. If it has yet to be satisfactorily resolved, then this, Pääbo suspects, is because it has never been properly framed. The question of what defines the human has, of course, been kicking around since Socrates, and probably a lot longer. They are attempts to solve a single problem in evolutionary genetics, which might, rather dizzyingly, be posed as: What made us the sort of animal that could create a transgenic mouse? In Pääbo’s mind, at least, these research efforts all hang together. A third team was slicing open the brains of mice that had been genetically engineered to produce a human protein. When I visited him in May, he had one team analyzing DNA that had been obtained from a forty- or fifty-thousand-year-old finger bone found in Siberia, and another trying to extract DNA from a cache of equally ancient bones from China. Each of the students painted a piece of the portrait, the over-all effect of which is a surprisingly good likeness of Pääbo, but in mismatched colors that make it look as if he had a skin disease.Īt any given moment, Pääbo has at least half a dozen research efforts in progress. Pääbo’s office is dominated by a life-size model of a Neanderthal skeleton, propped up so that its feet dangle over the floor, and by a larger-than-life-size portrait that his graduate students presented to him on his fiftieth birthday. ![]() He is tall and lanky, with a long face, a narrow chin, and bushy eyebrows, which he often raises to emphasize some sort of irony. Svante Pääbo heads the institute’s department of evolutionary genetics. A TV in the cafeteria plays a live feed of the orangutans at the Leipzig Zoo. (The pavilion is now empty.) In the lobby of the institute there’s a cafeteria and an exhibit on great apes. If you walk down the street in one direction, you come to a block of Soviet-style apartment buildings in the other, to a huge hall with a golden steeple, which used to be known as the Soviet Pavilion. The institute sits at the southern edge of the city, in a neighborhood that still very much bears the stamp of its East German past. The Max Planck Institute for Evolutionary Anthropology, in Leipzig, is a large, mostly glass building shaped a bit like a banana. ![]()
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