Interbreeding of Neanderthal and early humans happened frequently says study

Researchers have published the results of a new study that shows that breeding between Neanderthal and early humans was much more common than previously believed. Early humans and Neanderthal lived together for about 30,000 years and were certain to have had frequent contact in that span. Previously, researchers found that at least one pairing of a Neanderthal and an early human resulted in an offspring, that fact is reflected in the DNA of modern humans.

The scientists point out that about 2% of DNA in non-African humans today is Neanderthal in origin. Current research has found that some people in East Asia have up to 20% more Neanderthal DNA than people who are strictly European descent. Data for the study was pulled from the 1000 Genomes Project and measured the amount of Neanderthal DNA in the genetic material from volunteers.

The process involved separating the data into groups of people of European and Asian ancestry. Once that data was separated, evidence was found of multiple interbreeding events between early humans and Neanderthal. Researchers then created simulations that showed the outcomes of different numbers of mating events between the two groups.

That data was then fed into a machine-learning algorithm that showed DNA percentage patterns based on cross-breeding events that occurred. The results of that showed that many cross-breeding events between early human and Neanderthal in both East Asia and Europe had occurred.

This research was carried out by researchers Fernando Villanea and Joshua Schraiber from Temple University. The work was published in the journal Nature Ecology and Evolution. Other Neanderthal research conducted last year showed that they had had larger brains than modern humans.