A recent genetic study suggests that Neanderthals predominantly inherited modern human DNA from their female ancestors due to mating preferences within the ancient populations. Researchers at the University of Pennsylvania analyzed the genetic makeup of Neanderthals, focusing on the X chromosomes to uncover insights into their social behaviors.
The interbreeding between Neanderthals and modern humans occurred in the past when Neanderthals inhabited Europe and Asia, while modern humans originated in Africa. This genetic exchange left traces of Neanderthal DNA in non-African human populations.
The study specifically examined the X chromosome, which is unique as men possess only one, unlike other chromosomes found in pairs in both genders. By comparing the X chromosomes of ancient Neanderthal women to modern human women from sub-Saharan Africa, researchers discovered a significant presence of human DNA in the Neanderthal X chromosomes, especially in comparison to their autosomes.
The research team proposed that the unequal distribution of human DNA in Neanderthal X chromosomes could be attributed to mating preferences favoring individuals with more human ancestry. This unequal passing of the X chromosome from women to their offspring, compared to men, may have contributed to this genetic pattern.
Various factors, including mate preferences, migration patterns, and natural selection, likely influenced the observed biases in Neanderthal X chromosomes. Previous studies have also suggested implications of genetic mismatches between Neanderthals and humans on offspring health and fertility among ancient populations.
The findings shed light on the complex interactions and breeding dynamics between Neanderthals and modern humans, offering valuable insights into the genetic legacy of our ancient ancestors.