Experts Determine the Gender of an Extinct Hominin Species by Extracting Protein From Teeth Enamel of a Fossil

Experts applied paleo proteomics to find the gender of a fossil found in South Africa. This fossil belonged to a human relative, Australopithecus africanus, and was discovered in the Sterkfontein limestone caves, stated Live Science. This is the first time the technique has been used to find the gender of an individual from an extinct hominin species. Findings regarding how the method was used, and what result it produced have been published in the South African Journal of Science.

Paleoproteomics is a process in which ancient proteins trapped in tooth enamel are studied. The technique developed three decades ago, focuses on proteins because they can preserve genetic information longer compared to DNA. Before this study, the technique was used to get the genetic records of many ancient creatures like an 80 million-year-old Brachylophosaurus.

According to researchers, this particular fossil of A.africanus is the oldest specimen of a human relative to be going through this analysis. "To my knowledge, among the publicly shared hominin enamel proteomes, A. africanus is the oldest hominin to be subjected to palaeoproteomic analysis," study lead author Palesa Madupe, a postdoctoral researcher in the Section for Geogenetics at the University of Copenhagen shared.

Researchers associated with the study extracted around 100 peptides (short chains of amino acids present in proteins) from the tooth of one individual from A. Africanus species. The fossil was dated back to  3.5 million years ago, as per examinations. Experts found that many of these peptides belonged specifically to amelogenin, a protein important in normal tooth development. Since males and females, formulate this protein using distinct methods, researchers were successful in identifying the gender of this individual. As per their analysis, the individual whose peptides were garnered was a male. The examination was beneficial for researchers, because identifying the genders of such old fossils is not an easy task, because of their fragmentary nature. 

Sterkfontein limestone caves are part of a famous archaeological site in South Africa named 'Cradle of Humankind.' Researchers are trying to apply paleo proteomics to specimens of six hominin species, whose fossils have been identified in the region. Their objective is to understand how these species were different from each other using the results of this analysis. Researchers were ecstatic with the success of this method. They are now looking forward to applying it to subjects in more regions, and different climates. They believe this will help experts enhance their knowledge about human ancestors. "These are all incredibly exciting breakthroughs that are poised to revolutionize our understanding of human evolution," the researchers wrote.

The study was published in a special issue of the journal celebrating the 100th anniversary of the study that described "Taung Child." Taung Child was an ancient child's skull that was uncovered by quarry workers blasting a limestone cliff in South Africa. The famous fossil led researchers to discover that A. africanus was a human relative. The finding was a breakthrough for the time because it was the first ancient hominin to be found in Africa.