Archaic humans in Africa interbred with anatomically modern humans

Washington, Sept 8 (ANI): A new research has revealed that archaic humans, who lived somewhere in Africa during the last 20-60 thousand years, interbred with anatomically modern humans and transferred small amounts of genetic material to their offspring who are alive today,

"It appears some level of interbreeding may have occurred in many parts of the world at different times in human evolution," said University of Arizona geneticist Michael Hammer, who conducted the study with a team of evolutionary biologists, geneticists and mathematicians.

Hammer and team studied DNA sequence data from three sub-Saharan African populations: Mandenka, Biaka and San to test models of African archaic admixture.

The result gave the scientists confidence to infer that contemporary African populations contain a small proportion of genetic material-about 2 percent-that moved from a species of archaic humans into the gene pool of anatomically modern humans about 35 thousand years ago.

His work is the first to definitively suggest interbreeding between separate human forms inside of Africa.

Additionally, researchers discovered evidence that a distinct group of extinct archaic humans who lived in Southern Siberia, called 'Denisovans,' contributed genetic material to the genomes of present-day Melanesians.

"Given recent fossil evidence, however, the greatest opportunity for introgression was in Africa" where anatomically modern humans and various archaic forms co-existed for much longer than they did outside of Africa, according to the researchers.

"We estimate that the archaic DNA fragments that survive in modern African genomes come from a form or forms that diverged from the common ancestor of anatomically modern humans 700 thousand to 1 million years ago," said Hammer.

"This archaic genetic material is more prevalent in west-central African populations, possibly reflecting a hybridisation event or process that took place in central Africa.

"The populations that interbred were similar enough biologically so that they were able to produce fertile offspring, thus allowing genes to flow from one population to the other," he stated.

The finding was reported in Proceedings of the National Academy of Sciences. (ANI)