A recent genetic study suggests that Neanderthals predominantly inherited modern human DNA from the females in their families due to mate preferences. Researchers from the University of Pennsylvania reached this conclusion by analyzing the X chromosomes of Neanderthals and modern humans. The findings shed light on the social behavior of ancient populations.
Modern humans originated in Africa, while Neanderthals lived in Europe and Asia, leading to interbreeding between the two groups. As a result, all humans with ancestry outside Africa carry some Neanderthal DNA. Neanderthal genomes also contain traces of human DNA, although not evenly distributed.
The study focused on the X chromosome, which is unique as men have only one, unlike other chromosomes that come in pairs. By comparing Neanderthal and modern human women’s X chromosomes, researchers discovered significantly more human DNA in the Neanderthal X chromosomes, particularly in regions with less functional genes.
Possible explanations for this phenomenon included the effectiveness of human genes on Neanderthal X chromosomes and unequal interbreeding patterns favoring human DNA. Unequal passing of the X chromosome from women to offspring could also contribute to the higher presence of human DNA in Neanderthal X chromosomes.
The study suggested that mate preferences and genetic selection might have influenced the unequal distribution of human DNA in Neanderthal X chromosomes over generations. Additional factors, such as migration patterns and natural selection, could have played a role in shaping these genetic biases.
Experts found the study fascinating and noted that various factors could have impacted breeding patterns among Neanderthals. Previous research indicated potential challenges for Neanderthal-human hybrid offspring, highlighting the complexities of genetic interactions between the two groups. This understanding may have influenced Neanderthal mating behaviors and reproductive success.