Credit: Unsplash/CC0 public domainMultiple lines of evidence have confirmed that ancient hominins, known as Denisovans, interbred with modern human beings in the distant past. This is according to researchers. Researchers have now discovered that the Ayta Magbukon, a Philippine Negrito group, has the highest Denisovan ancestry. They actually have more Denisovan DNA that the Papuan Highlanders who were once the population with the highest Denisovan ancestry.Maximilian Larena, Uppsala University said that they made the observation despite the fact Philippine Negritos being admixed recently with East Asian-related group who have little Denisovan heritage. This resulted in a diluted level of Denisovan origins. Their Denisovan ancestry could be 46 percent higher than that of Australians or Papuans if we take out the East Asian-related ancestry of Philippine Negritos.Larena and her colleagues, including Mattias jakobsson, set out to determine the Philippines' demographic history. They analyzed approximately 2.3 million genotypes of 118 Filipino ethnic groups, including many self-identified Negritos, through a partnership between Uppsala University of Sweden and the National Commission for Culture and the Arts of the Philippines. High-coverage genes of Ayta Magbukon and AustraloPapuans were also included in the sample.According to the study, Ayta Magbukon has the highest level Denisovan ancestry worldwide. This is consistent with an independent admixture event that resulted in Negritos being derived from Denisovans. The data, together with the discovery of Homo Luzonensis, a small-bodied hominin suggests that multiple archaic species existed in the Philippines before the arrival of modern humans. These archaic groups could have been genetically related.Researchers conclude that these findings reveal a complex intertwined history between modern and archaic humans living in the Asia-Pacific region. They show how distinct Islander Denisovan communities were differentially mixed with incoming Australasians at different points and locations.Jakobsson stated that this admixture resulted in variable levels of Denisovan ancestry within the genomes of Philippine Negritos, and Papuans. "In Island Southeast Asia, the Philippine Negritos later admixed East Asian migrants with little Denisovan heritage, which further diluted their archaic ancestral ancestry. However, some groups, like the Ayta Magnukon, were only minimally mixed with the more recent migrants. The Ayta magbukon, for this reason, retained the majority of their inherited archaic tracts. They were also left with the highest Denisovan ancestry level in the world.Larena stated that sequencing more genomes will allow us to address multiple questions. She said, "By sequencing additional genomes in future, we'll have better resolution in answering multiple questions, including how the inheritance archaic tracts influenced biology and how it contributed towards our adaptation as species."Continue reading Modern humans have interbred with Denisovans twice throughout history.More information: Current Biology, Larena et al. : "Philippine Ayta possess the highest level of Denisovan ancestry in the world" DOI: 10.1016/j.cub.2021.07.022 Journal information: Current Biology , Larena et al. : "Philippine Ayta possess the highest level of Denisovan ancestry in the world" www.cell.com/current-biology/f 0960-9822(21)00977-5
