An ancient skull, found in China, suggests the inbreeding was quite common. According to a March 18 report by Live Science, the fossil helps to prove that inbreeding was common among our early human ancestors.
The skill is about 100,000 years old. It was found in Xujiayao in northern China. Although only fragments were found, those fragments show a now-rare deformity. The deformity, known as “enlarged parietal foramen,” only occurs in about one of 25,000 human births.
“I could have lived my entire life without knowing this,” Lloyd Cramer, from Oklahoma City, said. “I'm going to tell myself that the inbreeding was due to them not knowing they were related. I'd prefer not to have to think that it was because they wanted to have sex with family members. I will keep my blinders on when it comes to this.”
This congenital deformity is not lethal. It simply keeps the skull from forming completely. This is proven by the fact that the skull is believed to have been from an individual who lived to middle age.
Many skulls from the Pleistocene epoch (about 2.6 million to 12,000 years ago) have many genetic abnormalities, much like the skull. It is believed those genetic abnormalities were caused by inbreeding.