Wednesday, March 8, 2017
Melissa Davey - Aboriginal DNA study reveals 50,000-year story of sacred ties to land
A study of ancient Aboriginal hair samples has revealed distinct Aboriginal populations were present in Australia with little geographical movement for up to 50,000 years. The discovery of such a long, continuous presence in the those regions emphasised why land was so sacred to Aboriginal people, researchers said. The results emerged after researchers led by the University of Adelaide’s Australian centre for ancient DNA analysed the mitochondrial DNA from 111 hair samples collected during anthropological expeditions in the early to mid-1900s. The samples are stored at the South Australian Museum.
Mitochondrial DNA is the powerhouse that drives the conversion of food into energy, and is useful to researchers because it carries genetic material passed exclusively between a mother and her children, allowing maternal ancestry to be traced. Despite the age of the hair samples and the fact that they were collected under harsh environmental conditions, the researchers were surprised to find high concentrations of good quality mitochondrial DNA.
Their analysis found Aboriginal Australians are the descendants of a single founding population that arrived in Australia 50,000 years ago, while Australia was still connected to New Guinea. Populations then spread rapidly – within 1,500 to 2,000 years – around the east and west coasts of Australia, meeting somewhere in South Australia. One of the researchers, the geneticist Dr Ray Tobler, said the samples meant Aboriginal ancestry could now be genetically traced back in time to a point that pre-dated European colonisation, when Aboriginal people were still living in their traditional areas, supporting what the archeological evidence already shows.
Having the genetic information was crucial because after colonisation Aboriginal people were forced off country or forcibly removed from their families and scattered all over Australia, Tobler said. “If you want to do historical research on the connection between people and land you can’t do it using modern Aboriginal people because of that disconnection,” he said. “I have Aboriginal ancestry through my granddad but he never spoke about it because he was removed from his family. A lot of people in my situation interested in recording their history can do so through this project.”..