Erik Trinkaus, an anthropologist at Washington University, has found what he describes as "an abundance of developmental anomalies" in people that lived during the Pleistocene.

Hmm

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.

Evolution breeding out, alien testing - or perhaps due to solar radiation or even "electric universe" theory?