What was special with Josef Mengele's skull?

Forensic doctor Daniel Muñoz shows the skull of Nazi war criminal Josef Mengele to medical students in São Paulo, Brazil. Photograph: Andre Penner/AP. read more

Richard Helmer (right) with Ali Hameli (left) and the skull of Josef Mengele, as prepared for the demonstration of face–skull superimposition, Medico-Legal Institute labs, São Paulo, Brazil, June 1985. Courtesy of Maja Helmer. read more

The skull of Josef Mengele on display for reporters and news crews, 6 June 1985 in Embu, Brazil. The Auschwitz doctor’s bones were unearthed in a small cemetery there in a grave marked “Wolfgang Gerhard.” Photo Robert Nickelsberg. Courtesy Getty Images. read more

Dr. Josef Mengele, the infamously monikered 'Angel of Death' of the Second World War, was notorious for his sinister experiments on twins at the largest Nazi concentration camp of Auschwitz, ostensibly in an effort to produce a master Aryan race for Adolf Hitler. read more