Neanderthals remain one of the great mysteries of human evolution. They are the human's closest relatives, but their habits elude us. We are learning more about our hominid cousins every day, but there is still so much we do not know, including the mystery of Neanderthal mating habits, as there is not a lot of evidence to describe what Neanderthal sex would have been like. Thankfully there are new advances in genetic paleontology shining a light on this elusive subject, and the discoveries surrounding ancient human mating rituals continue to develop.
Prehistoric intercourse was complicated, especially when navigating a mating scene that spanned multiple different hominid species. Scientists have uncovered proof that humans and Neanderthals likely mated with each other, and we're still feeling the effects of that crossbreeding today.
Even though modern humans and Neanderthals are completely different species, that did not stop the two from hooking up. We know for a fact humans and Neanderthals had intercourse with one another, as revealed with DNA testing. A genetic analysis run on the remains of a 40,000 year old human uncovered that 11% of his genome wasn't actually human, but Neanderthal. It's the highest concentration of Neanderthal DNA ever found in a human. There are even people alive today who have remnants of Neanderthal in their genes.
As it turns out, Neanderthal's passed on certain genes that can cause ulcers to generate on human genitalia. People with the Neanderthal gene HLA-B*51 are more likely to develop Behcet's disease, a condition that has several side effects like ulcers on the mouths and genitalia, inflammation, and blindness. Behcet's isn't the only condition linked to Neanderthal DNA; Crohn's disease, lupus, and diabetes are all ailments that are influenced by the remnants of ancient DNA.
Neanderthals and modern humans differ in many ways, and one of the most severe differences is our perspective on relationships with close relatives. A female Neanderthal toe bone was discovered in a Siberian cave, and a genetic analysis uncovered the Neanderthal's parents were actually close relatives. It's likely the parents were half-siblings, an aunt and her nephew, or vice versa. Scientists confirmed the level of inbreeding in this particular specimen was unusually high for any species, suggesting this was far from a fluke incident.
Interbreeding between humans and Neanderthals was not an isolated occurrence. According to various DNA evidence, it appears this interspecies love affair was ongoing since at least 100,000 years ago. The two species mingled and mixed for an estimated 60,000 years, producing fertile offspring whose genetic lineage continues to this day. It is believed thousands of these couplings happened over the course of this timeline. This revelation actually revolutionized our knowledge of our own history and made it clear that homo sapiens must have left Africa earlier than we thought. Since Neanderthals never lived in Africa, evidence of human/Neanderthal mixing proves humans migrated to Eurasia at least 100,000 years ago.