Homo sapiens and Neanderthal interbreeding

The modern humans are supposed to have intermixed with Neanderthals and gene flow occurred among them around 60,000 to 50,000 years before present in the Southwest Asia region.On the possibility of regular mixing of modern humans with the extinct relatives like Neanderthals in Eurasia,VivianeSlon of the University of Tel Aviv in Israel said that it might have happened in different times and at different places over and over again. Though there is no iota of doubt that humans originated in Africa and dispersed in waves out of it to Asia and Europe, yet the latest DNA analysis of present-day humans show that it isn’t entirely African ancestry but the early Eurasianscontained some amounts of Neanderthal DNA as well.

A DNA study by Dr. Fu and colleagues in 2015 on skeletal remains of a Romanian individual some 40,000 years before present had shown to have Neanderthal ancestors for the past four to six generations suggesting interbreeding of this person with Neanderthals. This was the time when Neanderthals were vanishing and becoming extinct. But whether one finding of interbreeding of humans with Neanderthals during the abovementioned period in Europe can be taken as a widespread intermixing phenomena or not.BachoKiro cave site in Bulgaria yielded skeletal remains of three individuals who belonged to the period around 43000 years ago whose DNA analysis confirmed that these were Homo sapiens but had Neanderthal ancestry. The findings from this site reported earliest known burials, artifacts and ornaments belonging to Aurignacian culture.  Hajdinjak, Mafessoni, and Pääboof Max Planck Institute (Nature, 7^th April, 2021) opined from genome-wide datathat these three individuals show a close affinity withpresent day and ancient human populations of America and Asia. This study throws light on the spread and migration of modern humans.  According to thegenomic evidence,the authors suggested a continuity between the earliest modern humans in Europe and later people in Eurasia. The modern non-African humans possess about 2% of Neanderthal ancestry whereas those of BachoKiro cave have 3.4 to 3.8 % of it and their chromosomal lengths were also comparatively larger instead of shortening from generation to generation. There is not enough evidence form Eurasia and Europe regarding the timeline of admixture between humans and Neanderthals and more archaeological evidence from various areas is required to clear the picture on this issue.