Sunday, May 16

Modern humans and Neanderthals mixed more often than previously thought

There are few studies on the role that early modern humans played in the evolution of later populations.

There are few studies on the role that early modern humans played in the evolution of later populations.

The journal Nature publishes two studies on Wednesday suggesting that modern humans mixed with neanderthals in Europe more frequently than previously believed, while reinforcing theories about the evolution of successive populations on the continent.

The first work, developed by experts from the Max Planck Institute for Evolutionary Anthropology (Germany), starts from the analysis of the genome of the oldest known modern human remains, which offers clues about their first migrations in Europe and describes groups of populations complex and varied.

The researchers recall that the oldest remains of modern humans, the homo sapiens emigrants from Africa, they were found in the cave of Bacho Kiro, in present-day Bulgaria, and have, according to radiocarbon dating, between 45,930 and 42,580 years.

Until now, they specify, it has not been clear what was the extent of the interactions that occurred between these sapiens and Neanderthals, present until about 40,000 years ago.

In addition, they warn, there are few studies on the role of early modern humans in the evolution of later populations.

Therefore, the sequence analysis of the nuclear genome of specimens from the Bacho Kiro cave sheds light on the identity of their ancestors, as well as their connections with modern-day humans, highlights the main author of this study, Mateja Hajdinjak.

His team found that, of those remains, the three oldest individuals share more genetic variants with current populations East and Central Asia and America than with West Eurasian populations.

These individuals have between 3 and 3.8% Neanderthal DNA, while the distribution of this genetic material in those genomes suggests that those early modern humans had Neanderthal ancestors “six or fewer generations ago.”

Consequently, the authors note, these data point to modern humans intermingling with Neanderthals in Europe more often than previously thought.

The second study published today by Nature, developed by another group of experts from the Max Planck Institute, presents the reconstruction of the genome of a skull found in modern-day Czechia from the presence of Neanderthal DNA, which could be more than 45,000 years old.

The genomic sequence of this skull, which belonged to a woman and was found at the Zlatý kůň site, indicates that it has 3% Neanderthal ancestry.

Likewise, Kay Prüfer, the lead author of the study, observes that he may have belonged to a population group that does not appear to have contributed genetically to later populations in Europe or Asia, that is, it formed before the ancestors of Europeans. and modern Asians parted ways.

Experts explain that it has not been possible to date the Zlatý kůň skull with the radiocarbon technique because the fossil was “contaminated with bovine DNA”.

However, the length of Neanderthal segments present in the genome is greater than that detected, for example, in the genome of the oldest modern human known to date, found at the Ust Ishim site (Siberia) and estimated to be about 45,000 years old.

This suggests that the individual from the Czech Republic could belong to one of the first groups of humans to populate Eurasia after leaving the African continent.

Leave a Reply

Your email address will not be published. Required fields are marked *