Ancient tooth proteins reveal how mysterious human species are related to us

While it is difficult for scientists to piece together a complete history of human evolution from piles of old bones, they have now developed a new method to study a protein from human tooth enamel from 800,000 years ago, which could help put it on a genealogical map,media reported. Although Homo sapiens is the only human species still alive today, the road to this place is paved with extinct relatives.

Ancient tooth proteins reveal how mysterious human species are related to us

Untangling their connection is a problem scientists have been trying to solve. The timeline is usually determined by a variety of chronadating processes, including the bones themselves and the sedimentary layers in which they are located. This timeline is then used to determine the relationships between species and to track the evolution by examining the structure and characteristics of the bones.

Ancient tooth proteins reveal how mysterious human species are related to us

In the new study, researchers from the University of Copenhagen used a new tool called paleote omicology to obtain more accurate images. This involves sequencing proteins from ancient relics and their effect on samples that are too old to have complete DNA. This time, the team applied it to the teeth of a mysterious ancient human species called the Homo Anteceor, which is 800,000 years old.

Ancient tooth proteins reveal how mysterious human species are related to us

The remains of the Pioneers

Study co-author Jesper Velgaard Olsen said: “Using state-of-the-art mass spectrometry technology, we identified the sequence of amino acids that remain in proteins in the pioneer tooth enamel. We can then determine the genetic relationship between the ‘read’ ancient protein sequences and the genetic sequences of other primitive humans, such as Neanderthals and Homo sapiens. “

In this way, the team was able to determine the position of the pioneers in the lineage in a more accurate manner than ever before. It has previously been suggested that the species was the last common ancestor of our modern humans, Neanderthals and Denisovans. But the new study suggests that while we are close relatives, we did not evolve directly from the forerunners — the pioneers were less like great-grandfathers than “uncles.”

Frido Welker, lead author of the study, said: “The analysis of ancient proteins provides evidence of the close relationship between human ancestors, us (Homo s) and Neanderthals and Denisovans. Our findings support the view that ancestors were sisters of Homo sapiens, Neanderthals, and Denisovans. “

Applying paleoteomics to other fossils could reveal other new details about human ancestors, the team said.

The study was published in Nature.