Using the genomes of two ancient hominids unearthed in Brazil, a team of paleobiologists has discovered that ancient South Americans had Neanderthal and Denisovan ancestry, revealing the complex interbreeding of both species with sapiens. (modern humans).
The neanderthals they were a human population that arose 400,000 years ago and went extinct 40,000 years ago. They first lived in Europe and then spread to Asia.
The Denisovans they also inhabited Eurasia, however, their existence was shorter, between 50,000 and 30,000 years ago. This group is still a complete mystery, having been identified just two decades ago from DNA sequences from a fossil finger.
The research, published in the Proceedings of the Royal Society Publishing, also provides evidence that ancient humans not only migrated from north to south along the coasts of the Pacific Ocean and settled in the Andes, but that, much later, a group began the opposite tour, but along the Atlantic coast.
This migration from south to north would have happened 1,000 years ago and would have consisted of a route of 5,277 kilometers, from Uruguay to Panama.
An intricate migratory journey
The researchers, belonging to the Florida Atlantic University (FAU) and Emory University, analyzed the DNA of two individuals from 1,000 years ago in Pedra do Tubarão and Alcobaça (northeast Brazil). They obtained their complete genomes and compared them with the genes of other ancient humans from the Americas and the world.
Thus, for example, they discovered that the ancient individuals of Uruguay and Panama had greater Denisovan ancestry than Neanderthal.
“The mixing must have happened much earlier, perhaps 40,000 years ago. The fact that the Denisovan lineage persisted and its genetic signature made it an ancient individual from Uruguay that is only 1,500 years old suggests that it was a large mixing event between a population of humans and Denisovans,” said archaeologist John Lindo, one of the from the study authors.
They also identified that the genome of an ancestor from Panama was similar to that of ancient humans in Australia and Papua New Guinea (Australasia).
“There is a whole Pacific Ocean between Australasia and the Americas, and we still don’t know how these ancestral genomic signals appeared in Central and South America without leaving traces in North America,” said Andre Luiz Campelo dos Santo, first author of the research.