Ancient DNA from 45,000-year-old human remains has revealed a previously unknown component of human evolution.
Dr. Yassine Souilmi, Group Leader at the University of Adelaide‘s Australian Centre for Ancient DNA, co-led the new Nature Ecology and Evolution study.
“It was commonly believed the genetics of our human ancestors didn’t alter due to environmental constraints as much as other animals, due to our increased communication abilities and ability to build and use tools,” Dr. Souilmi added.
However, by comparing present genomes with ancient DNA, we found over 50 occurrences of an initially rare and advantageous genetic mutation becoming prevalent across all ancient human tribes.
Humans have conflicting evidence for adaptive genetic change, unlike many other species. “This discovery contradicts the current idea of human adaptation and provides a new and intriguing perspective on how humans adapted to new environmental pressures as we expanded throughout the earth.”
Lead author Dr. Ray Tobler, an adjunct fellow at the University of Adelaide and a DECRA fellow at the Australian National University, said ancient DNA has helped reveal human evolution.
“We thought past mixing events between human tribes would have hidden genetic changes in present-day human genomes,” Dr. Tobler stated.
“We investigated DNA from more than 1,000 ancient genomes, the oldest roughly 45,000 years old, to discover if certain types of genetic adaptation had been more widespread in our past than studies of modern genomes had suggested.”
Professor Christian Huber, a senior author of the research publication, is an adjunct fellow at Adelaide University and an assistant professor at Penn State University.
Professor Huber said ancient genomes were important because they preceded big historical mixing episodes that radically impacted present-day European genetic origins.
“This analysis recovered historical adaptation indicators that are unseen in normal genomic analysis.”
The Australian Centre for Ancient DNA, founded in 2005, leads the world in sophisticated ancient DNA methods for evolutionary, environmental, and conservation applications.
The Mayo Clinic, Garvan Institute of Medical Research, Max Planck Institute for the Science of Human History in Germany, the University of New South Wales, and Massey University in New Zealand all contributed to the publication.
