The theory of a Neanderthal-human hybrid may now be considered scientific fact after evidence that was presented in northern Italy earlier this week revealed a distinctive crossover of genetic traits between the two species. A paper published on PLoS ONE discusses aspects of the discovered skeletal remains, including fragments from a jawbone and cranium, which point to the gradual crossbreeding of the Homo neanderthalensis with the modern Homo sapiens, or humans.
Further analysis is needed to cement the theory, but if proven correct, the 30,000 to 40,000 year-old remains will be of the very first hybrid in existence. Previously, genetic research had revealed that humans with DNA of European and Asian descent were between one and four percent Neanderthal. However, the evidence up until now was not conclusive and based solely on “ambiguous fossils.” The Neanderthal genetic line declined and eventually vanished around 30,000 years ago through a mix of interbreeding and human conquest.
The fossilized jawbone and cranial fragments was discovered in 1957 in Riparo Mezzena in the Monti Lessini mountains of northern Italy. Researchers analyzed the mitochondrial DNA (mtDNA), which revealed the Neanderthal lineage. However, the shape of the bone possessed characteristics more closely in line with traits of the modern human. Since mitochondrial DNA is passed down from mother to child, researchers have concluded that the remains are from a “female Neanderthal who mated with male Homo sapiens.”
“From the morphology of the lower jaw, the face of the Mezzena individual would have looked somehow intermediate between classic Neanderthals, who had a rather receding lower jaw (no chin), and the modern humans, who present a projecting lower jaw with a strongly developed chin,” said study co-author Silvana Condemi, an anthropologist at the University of Ai-Marseille, to Discovery News.
Homo sapiens migrated into the Riparo Mezzena region approximately 41,000 years ago where the Neanderthal already possessed an established culture. The two species coexisted for a lengthy duration before the modern human finally dominated the territory and phased out the Neanderthal lineage. Some experts within the scientific community still doubt the hybrid theory pointing to evidence from Spain, which suggests the Neanderthal species was actually extinct thousands of years before the arrival of the modern Homo sapiens. Genetic similarities, they say, are the result of common ancient ancestors.
The debate and research of the Neanderthal-human hybrid theory will, no doubt, continue. To read the full article published on PLoS ONE visit http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0059781.
