Paabo sequenced the genome of the Neanderthal and also discovered the previously unknown hominin Denisova. His work showed the genomic changes that came to differentiate humans and their closest cousins. He also showed that both Neanderthals and Denisovans contributed genes that still exist in modern humans.

“By revealing genetic differences that distinguish all living humans from extinct hominins, his discoveries provide the basis for exploring what makes us uniquely human,” the Nobel committee said.

Their work has not only taught scientists more about the Neanderthals, but it is also credited with having helped modern medicine during the COVID pandemic.

“From the genome of Neanderthals, we can learn what defines modern humans. One of our big findings was that a major risk factor for severe COVID is a gene variant that has come down from the Neanderthals,” said Zeberg. “And we believe a million people have died [with COVID] because of that gene variant.”