According to the ancient fossils from the early human ancestors were pretty closely widespread sexual relationships. The proof of this fact are the remains of a human skull age of about 100,000 years, which archaeologists have found near a place called Hudzhiayao in the north of China. Researchers claim the remains, that the owner of the skull were found rare birth defects that are likely to have arisen as a result of incest.
This skull — just one of many other examples of the remains of ancient people, who were also detected congenital anomalies. The head of research, an anthropologist at Washington University Trinhaus Eric said that these tribes small certainly lived apart, so they have been developed closely link.
The upper part of the test results skull hole. This is evidence of the disease, which is known as "the increased parietal hole" — the symptom is similar to the modern eponymous disease arising as a result of a rare genetic mutation. Genetic defects prevent the normal development of bones, because of what the human embryo does not close the skull. To date, these mutations are rare — one of 25,000 babies.
The man who owned the cranium, lived to middle age, and it means that the defect was not fatal. The deformation of the skull sometimes leads to cognitive impairment, but in this case, these effects have been minimal.
Discovered the skull of people who lived during the Pleistocene (2.5 million to 12,000 years ago), show an unusually large number of these genetic defects. In addition, scientists sometimes encountered such variations in the skeletons Homo Erectus, who lived in the early Stone Age.
As Eric said Trinhaus, such distribution of deviations from the ancient people supports the theory that in the period of human evolution, people lived very small groups and, therefore, welcomed the related sexual relations. However, scientists have noted that there is still not clear how long this took place, and it is unlikely it will be possible to find out.
Translation Sergei Vasilenkova
See also: The Nature of Antarctica, Secrets of ancient pyramids.