Proteins makes 1.7 million years talk as much as the DNA

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The ancient DNA offers valuable information about the evolution of life on Earth, including our own steps as a species. However, it is fragile, and its procurement is limited in time. The genome oldest sequenced until now is of a horse that lived about 700,000 years in Canada, recovered from a bone frozen into the permafrost near the Arctic. And among the human family, of a Homo heidelbergensis, a relative who lived in the Sima de los huesos of Atapuerca ago 400,000 years.

Now, a new research published in the journal “Nature” has blasted the record of reading of genetic data to the sequence proteins in the tooth of a rhinoceros, , who lived about 1.7 million years ago in Dmanisi, Georgia. Nothing less than a million years before the horse is canadian. The results, say the researchers, open the door to a “revolution” in the study of the evolution from ancient times that could also change what we know about our own origins.

The international team, formed by 48 researchers including two research professors ICREA Catalan Institute of Human Palaeoecology and Social Evolution (cr lation) in Tarragona, spain, used an innovative technology called mass spectrometry to analyze the tooth of a ‘ Stephanorhinus etruscus, a rhinoceros now extinct, which lived in Eurasia during the Pleistocene. The fossil was discovered in the archaeological site of Dmanisi, Georgia.

The results allowed to know new facts about the lineage of this two-horned rhinoceros and two and a half meters in length, adapted to open spaces, graceful and habits runners. For example, that corresponds to a sister group of the woolly rhinoceros, and that it “has to the of Sumatra, in danger of extinction, as the living relative nearest”, explains Jordi Agustí, the cr lation.

Reconstruction of ‘ Stephanorhinus etruscus – Mauritius AntónMás ago in the human evolution

The fit of the evolutionary lineage of a species may seem a small step, but the impact of sequence proteins from fossils as old are many. While the DNA only seems to survive for a few hundreds of thousands of years, the proteins in good condition can hold millions of years. And the information that is obtained from them is equivalent to that which would provide the DNA if it were so stable. “Since then, the proteins cannot reconstruct an individual, but to establish relations of some groups with others,” explains Agustí. In addition, the tooth enamel is a durable material, abundant in fossils, which provides more genetic information than the collagen, the only other protein up to now recovered from fossils more than a million years.

This technique could allow scientists from around the world to build a larger image and accurate picture of the evolution of hundreds of species, including our own. The DNA data that tracked genetically human evolution only cover the past 400,000 years. But the lineages that led to modern humans and the chimpanzee, the living species genetically closest to us, they were separated about six or seven million years, which means that scientists do not currently have genetic information for over 90% of the evolutionary path that led to the emergence of Homo Sapiens.

Neither have a good understanding of the genetic links between us and extinct species such as Homo erectus, the oldest hominid with body proportions of modern similar to our own, because all that is currently known is based almost exclusively on anatomical information, not genetic information.

For this reason, the authors believe that their results “will revolutionize the methods of investigation of the evolution” , as he says one of the authors main article, Eske Willerslev, a researcher of the universities of Cambridge and Copenhagen. In a similar way it is expressed Agustí: “The fossil (rhino) comes from Dmanisi, a place where you have found the hominid more ancient Eurasia, the first that left Africa. It has opened a path of research fantastic,” he stresses.