Here’s what you’ll learn when you read this story:

• Researchers deciphered genetic data to discover two distinct settler groups dispersed into what is now New Guinea and Australia.
• The data supports the “long chronology” view that modern humans arrived at what was known as Sahul 60,000 years ago.
• Early voyages happened during a much different world landscape.

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The hot debate over just how—and when—the human population in what is now Australia and New Guinea formed took a major step toward the “long chronology” camp with new research claiming that genetic data shows two distinct groups of settlers dispersed into the region from what is now Southeast Asia roughly 60,000 years ago.

According to a new study published in the journal Science Advances, a team led by the University of Southampton’s Centre for Maritime Archaeology and University of Huddersfield’s Archaeogenetics Research Group posited that DNA research shows at least two dispersal routes into what was then Sahul, with both groups arriving around the same time.

“This is a great story that helps refine our understanding of human origins, maritime mobility, and early seafaring narratives,” Helen Farr, Southampton professor, said in a statement. “It reflects the really deep heritage that Indigenous communities have in this region and the skills and technology of these early voyagers.”

The team analyzed roughly 2,500 mtDNA genomes to build a tree and date lineages from varying regions. Using the mtDNA inherited only from the mother, the sequencing can recreate the maternal genealogy in great detail. The findings showed that the most ancient lineages in the Aboriginal Australians, New Guineans, or both, but nowhere else, dated to around 60,000 years ago, supporting the long chronology of population growth, even as the short chronology view of landfall no more than 50,000 years ago has been gaining popularity.

As all DNA changes gradually over time, the researchers used the molecular clock approach to date lineages from each region. The ancestry of the most ancient lineages traces back to Southeast Asia, with the largest group from northern Indonesia and the Philippines and a smaller group from southern Indonesia, Malaysia, and Indochina, suggesting two distinct routes into Sahul.

“Our results indicate that Aboriginal Australians along with New Guineans have the most ancient unbroken ancestry of any group of people outside of Africa,” Martin Richards, Huddersfield professor, said in a statement.

The authors wrote in the study that “this timescale is contrary to recent estimates,” but better meshes with the fossil and archaeological record. The study authors noted that during the last Ice Age the sea levels were much lower than they are today, and New Guinea and Australia were both part of the Sahul landmass, making seafaring more plausible even if still impressive.

While the data from the two dispersal groups into Sahul trace back to Asia, they both ultimately link to Eastern Africa roughly 75,000 years ago. The authors believe the two groups were from the same dispersal from Africa, splitting off before they traveled to Sahul. Richards told *Live Science *that along the way the traveling group likely met up with archaic humans, including “the hobbit” H. floresiensis, at some point in the journey.

“We feel that this is strong support for the long chronology,” Richards said. “Still, estimates based on the molecular clock can always be challenged, and the mitochondrial DNA is only one line of descent. We are currently analyzing hundreds of whole human genome sequences—three billion bases each, compared to 16,000—to test our results against the many thousands of other lines of descent throughout the human genome.”

Tim Newcomb is a journalist based in the Pacific Northwest. He covers stadiums, sneakers, gear, infrastructure, and more for a variety of publications, including Popular Mechanics. His favorite interviews have included sit-downs with Roger Federer in Switzerland, Kobe Bryant in Los Angeles, and Tinker Hatfield in Portland.