https://phys.org/news/2018-11-anthropologist-high-developmental-anomalies-pleistocene.html

Trinkaus found that among the fossil samples was evidence of 75 abnormalities. He also found that approximately two-thirds of those anomalies showed up in less than 1 percent of modern humans. He also found that the abnormalities came about due to a variety of ailments such as blood disorders or hydrocephaly—but a lot of them could not be traced to a cause. He suggests the number of abnormalities is extremely high for such a small group of fossils.

Trinkaus suggests inbreeding is one of the more likely reasons for such a high number of abnormalities—hunter-gatherer groups of the time are believed to have been rather small, increasing the odds of inbreeding. He also suggests that it is possible that individuals with such abnormalities received special treatment during burial, which increased the odds of their remains surviving to the modern age for analysis.

                                                            
                                    
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