Africa | Central Africa Society | Science - Education African "Pygmies" genetically isolated for 60.000 yearsafrol News, 15 April - According to new research into the genetics of Africa's so-called "Pygmies", their ancestors separated from other African peoples around 60,000 years ago, developing into a separate culture and genetic pool.
The international study, led by researchers at the Institut Pasteur in Paris and published in the journal 'PLoS Genetics' earlier this month, looked into the genetic variations among the distinct "Pygmy" peoples populating large part of Africa, comparing these with the genetics with other peoples of Africa. They made two important findings.
The research concludes that the ancestors of present-day African "Pygmies" and African peoples developing farming and livestock cultures separated around 60,000 years ago. Also, the study concludes that all African "Pygmies", inhabiting a large territory extending west-to-east along Central Africa, descend from a unique population who lived around 20,000 years ago.
Current "Pygmy" cultures are characterised by a forest-dwelling hunter-gathering lifestyle and distinctive cultural practices in addition to physical traits such as a low stature.
Two groups of "Pygmy" populations live in the African rainforests: the "Western Pygmies" and the "Eastern Pygmies". The common origins of the two groups of "Pygmies", separated by thousands of kilometres, have been long debated, and their relationships with neighbouring farmers remained obscure.
The researchers, led by Lluis Quintana-Murci, studied the genetic profile of twelve populations of "Pygmies" and neighbouring farmers dispersed over the African continent. Using simulation-based procedures, they determined that the ancestors of "Pygmy" hunter-gatherers and farming populations started to diverge around 60,000 years ago, coinciding with a period of important human migration both within and outside Africa.
Much later, around 20,000 years ago, Western and Eastern "Pygmies" separated, concurrently with a period of climate change leading to large retreats of the equatorial rainforest into refugia.
The common origin of all "Pygmies" unmasked in this study led researchers to conclude that "they have probably inherited their distinctive shared physical traits, such as low height, from a common ancestor, rather than by convergent adaptation to the rainforest."
However, complete genome-wide profiles of these populations were now needed, researchers hold, "both to characterise more precisely their demographic history and to identify genes involved in the adaptation of these populations with different lifestyles to their specific ecological habitats."
By staff writer © afrol News |