Scientists analyze tooth to find new clues about our prehistoric relatives

Scientists have finally come to know who exactly the Denisovans were. This has been possible only because of a single tooth.

Scientists came to know about Denisovan, one of our distant cousins and an extinct hominoid species, in 2008 when a portion of a finger bone and a fossilized tooth were discovered at the Denisova Cave in southern Siberia’s Altai Mountains. Then in 2010, archeologists unearthed another fossilized tooth.

Now, an analysis of one of those molars has thrown up an unprecedented insight into our prehistoric relatives. The entire analysis has been published in the Proceedings of the National Academy of Sciences, on Monday.

According to the research, the Denisovans might have interbred with the early Homo sapiens, Neanderthals and one more group of prehistoric hominins, which has not yet been identified. Max Planck Institute for Evolutionary Anthropology geneticist Svante Pääbo, who happens to be one of the coauthors of the study, said that this finding shows that the Denisovans although are close relatives of the humans, cannot be tagged as human ancestors.

During the analyses, Pääbo, and his co-researchers used a sterile dentistry drill to dig out the tooth’s DNA, which they are referring to as Denisova 8. The tool allowed them to pull out a tiny portion of the materials hidden inside the fossil. This step of extraction was followed by sequencing of the DNA obtained from the molar.

The analysis revealed that Denisova 8 is as many as 110,000 years old, which means it’s much older than the finger fossil and the other molar. Analyses of those two objects revealed that they are around 50,000 years old.

Pääbo stated that these revelations indicated that one among the three creatures studied by the scientists lived almost 60,000 years before the other two creatures. According to him, this finding shows that the Altai Mountains were inhabited by the Denisovans for a very long time, and if that was not the case these human relatives surely inhabited the place periodically over a significantly long period.

Scientists also think that these prehistoric human relatives possibly moved further south beyond the southern territories of Siberia. They said that evidence of that migration can be found today in modern-day Polynesians, New Guineans, Asian people, and Australian Aborigines in the form of partially identical DNA.