Scientists have used DNA in hair samples collected across Australia during the last century to determine that Australia’s Aboriginals have been inhabiting roughly the same regions on the continent for the last 50,000 years, a finding which underlines the importance of the land to Aboriginal communities, say the researchers.
“This is unlike people anywhere else in the world and provides compelling support for the remarkable Aboriginal cultural connection to country,” says Dr. Alan Cooper, Director of the University of Adelaide’s Australian Centre for Ancient DNA (ACAD) and co-author of the new study published in the journal Nature.
Part of the Aboriginal Heritage Project, the research consists of DNA analysis of 111 hair samples collected during a series of anthropological expeditions across Australia between 1928 and the 1970s. The DNA evidence led researchers to conclude that all Aboriginals, the first humans to populate Australia, are likely descended from a single founding group which travelled from New Guinea, once connected by land with Australia, and quickly spread across much of the continent. The researchers say that after colonization, strong regional population patterns were established, which remained much the same over thousands of years.
“Reconstructing the genetic history of Aboriginal Australia is very complicated due to past government policies of enforced population relocation and child removal that have erased much of the physical connection between groups and geography in Australia today,” says Dr. Wolfgang Haak, study co-author, formerly of ACAD and now at the Max Planck Institute for the Science of Human History in Germany.
The findings point to a surprising lack of mixing between Aboriginal populations of Australia, an uncommon phenomenon when compared to the migratory patterns identified on other continents.
Speaking to the New York Times, Dr. Cooper says that the lack of established agriculture among Australia’s aboriginals explains the difference. When agrarian societies grow, they eventually need to spread to other lands, often spurred on by crop failures that cause mass migration. Australia’s Aboriginal population did not take up farming thousands of years ago but stayed nomadic. “If you don’t have cheap carbohydrates, you don’t increase in population size,” Dr. Cooper says.
“We’re hoping this project leads to a rewriting of Australia’s history texts to include detailed Aboriginal history and what it means to have been on their land for 50,000 years,” says Dr. Cooper.
“That’s around 10 times as long as all of the European history we’re commonly taught.”
Human settlement of the Americas, by contrast, has been estimated to have occurred in the range of 20,000 years ago at the end of the Wisconsin Glaciation when the great ice sheets that covered much of North America began to retreat.
Much of the evidence gathered so far points to an arrival date of about 14,000 years ago, yet just recently researchers at the University of Montreal published their work on materials uncovered in the area of Old Crow, Yukon, which they say set the arrival date back thousands of years. Carbon-dated bone fragments from the Bluefish Caves are said to bear distinctive signs of being cut into by human tools as early as 24,000 years ago.