Research published this week by Nature has confirmed Australia's aboriginal people are the Earth's most ancient civilization. "A Genomic History of Aboriginal Australia" is a world-first genomic study that helps reveal how ancestors of today's aboriginals reached what is now Australia about 58,000 years ago.
Led by Professor Eske Willerslev from the University of Cambridge, the study was co-authored by elders from indigenous communities around Australia. The team was able to sequence the genome of 83 aboriginal people, as well as 25 Papuans from the New Guinea highlands. Researchers collected saliva from widely dispersed geographic and linguistic groups to retrieve the DNA. Previously, only three aboriginal Australian genomes had been sequenced.
Prior to this study being published, some scientists had debated whether or not modern aboriginals are the descendants of ancient tribes who first populated Australia. This research, the most comprehensive genomic study of indigenous Australians to date, also helps to confirm that all humans share the same common ancestors from a single African migration event.
That event occurred when both Papuan and Aboriginal ancestors left Africa as part of a larger group of migrants around 72,000 years ago, then split with that main group of early humans about 58,000 years ago. Probably the first group of humans to cross an ocean, they reached "Sahul"—the supercontinent that was made up of modern day Tasmania, Australia, and New Guinea together—and then split apart about 37,000 years ago. The supercontinent only split up around 8,000 years ago.
"Australia has one of the longest histories of continuous human occupation outside Africa, raising questions of origins, relatedness to other populations, differentiation, and adaptation," the study concludes. "We find that Aboriginal Australians and Eurasians share genomic signatures… a common African ancestor."
As the research also shows, aboriginal civilizations have lived in Australia for so long that they've been able to adapt biologically to its environment. This means that groups living in different parts of the country adapted in different ways according to weather conditions. Because they were so geographically isolated from one another—Australia's landmass being particularly vast—genetic diversity between different tribal groups is huge. Aboriginal Australians living in desert regions, for example, were able to withstand sub-zero night temperatures without increasing their metabolic rates. Europeans can't do this.
The publication of the research about human migration comes at a poignant time, with government immigration policy making headlines in Australia and around the world. Yesterday, Essential Research published the finding that 49 percent of Australians support a ban on Muslim immigration.
So if you're afraid of immigrants, perhaps consider this—you're a fairly recent arrival on land owned by the oldest-living civilization on earth.
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