The Aboriginal and Torres Strait Islander peoples of Australia have one of the oldest histories of any group of people living outside of Africa. The general consensus is that modern humans reached the continent around 50,000 years ago, tens of thousands of years before humans even managed to populate Europe. There have, however, been questions about just how isolated the Aboriginals have been during this long history, and whether there were later influxes of people.

A new study looking into the genetic history of Aboriginal men has seemingly managed to answer this, at least for male descendants. Researchers have sequenced the entire Y chromosome of Aboriginals for the first time, and found that it has indeed remained isolated for the 50,000 years that humans have been in Australia, with no evidence of any other migration adding to the gene pool. This contradicts a previous study that suggested that around 5,000 years ago there was a prehistoric influx of people in Australia from the Indian subcontinent.   

^{The dingo is not technically native to Australia, though it has lived there for thousands of years. John Carnemolla/Shutterstock}

“We worked closely with Aboriginal Australian communities to sequence the Y chromosome DNA from 13 male volunteers to investigate their ancestry,” explains Anders Bergstrom, who co-authored the study published in Current Biology, in a statement. They found that this section of the Aboriginal DNA was highly distinct from the Y chromosome of Indians, results which “refute the previous Y chromosome study, thus excluding this part of the puzzle as providing evidence for a prehistoric migration from India,” says Bergstrom. “Instead, the results are in agreement with the archaeological record about when people arrived in this part of the world.”

Yet this still leaves another question unanswered. One of the reasons researchers thought that humans made a second migration a few thousand years ago was to explain just how dingos got to Australia. The dogs are not native to the continent and are actually thought to be descendant from domestic dogs brought to the island in prehistoric times that then returned to the wild. But who were the people who brought the dogs with them and when did they arrive? The new study seems to rule out an Indian origin for the wild pooches.

The researchers say that they would like to now expand the genetic study to look at the entire genome, which would allow them to delve into and explore the rich ancient history of Aboringal and Torres Strait Islander people, as well as rule out completely any other genetic influences before the modern era. They also note that further research is needed to finally figure out where the dingo is actually from, and what happened to the peoples who brought the animals with them. 

^{Main image: Rusty Stewart/Flickr CC BY-NC-ND 2.0}