Media ReleaseFrom: Massey University
Molecular anthropology investigators may sound like something straight out of science fiction, but their work is allowing us to uncover when our earliest ancestors moved out of Africa – and it may be earlier than we thought.
The timing and route taken by early humans from Africa to Europe, Asia and Oceania is hotly debated with some suggesting that non-Africans trace their ancestry back to a single migration event around 40,000 to 75,000 years ago, while others suggesting that the migration took place in distinct waves over time.
The new research, co-authored by Massey University Professor Murray Cox, adds fuel to the debate by uncovering an earlier and now largely extinct wave of humans that moved from Africa to Eurasia between 100,000 and 120,000 years ago – giving the wave theory further verification.
This group has so far remained anonymous to researchers through large-spread extinction of the people within it, but could not slip past the team of investigators, who used one of the most reliable recordings of human ancestry – our DNA. The secret lay in the genetic material of modern Papuans, which revealed at least two per cent of their genetic material is retained from the earlier population.
Professor Cox was able to supply and help analyse portions of the data required to make these conclusions. His advice, taken from his study of human groups across Indonesia, was particularly required around the history and interpretation of the islands of Southeast Asia and New Guinea region.
“The study is able to provide some remarkable results and puts forward a strong case for more investigations into the DNA of smaller, more remote ethnic groups,” Professor Cox says. “These are under-explored regions from a genetic standpoint, as traditional studies have focused mainly on the standard categories of Europeans, Asians and Africans. While these have been a treasure trove of knowledge of our early movements and makeup, it’s now time to cast the net wider and discover what these other regions have to tell us.”
Further studies will clarify the timing and route followed during such an early expansion and the data will be used to analyse modern human immunity to certain diseases or tolerance to certain substances.
“The unravelling of our evolutionary history will require more archaeological investigations and further genetic studies into more remote groups in order to give us the full picture. This data is just one small piece of a much larger modern biology puzzle – in our field we must rely on our fellow researchers to solve these mysteries as the data sets and manpower needed exceeds the capabilities of any one team studying any one location,” Professor Cox says.
The study, 'Genomic analyses inform on migration events during the peopling of Eurasia', appeared in Nature and was led by Dr Luca Pagani of the University of Cambridge and Dr Mait Metspalu of the Estonian Biocentre. It involved a dataset of 483 high-coverage human genomes [genetic material] from 148 populations worldwide, including 379 new genomes from 125 populations.