Homo sapiens’ Intermingling with Extinct Ancestors Longer than Previously Thought
Sunday, March 20, 2016
Homo sapiens’ Genes
A study published in the journal Science reports that our ancestors Homo sapiens had a long adventurous sexual history than what was previously thought. This has left an indelible mark on the human genome, many of which are involved in the immune system with some playing an important role in skin and hair biology.
This was claimed after the scientists analysed genetic information of about 1,500 people from different locations around the world. This led to the understanding that there were at least four interbreeding episodes, tens of thousands of years ago involving our cousins Neanderthals and the mysterious extinct human species Denisovans. People from the equatorial islands of Melanesia were the only population to possess Denisovan genetic ancestry, although they had a Neanderthal genetic history like most of the humans.
Non–Africans roughly had about 1.5 to 4% Neanderthal genetic ancestry whereas the African population was deprived of both the Neanderthal as well as the Denisovan ancestry because neither of these species was present on the African continent. The fact that the Denisovan remains are found only in northern Siberia but their genes are seen in people living far away in Melanesia suggests their broad geographic range across Asia. Researchers also detected a gene from an unknown source, which throws light on at least four species of hominins (our species and extinct human species) living and interbreeding at the same time over the last 100,000 years.