Thinking in vain...

Now, a historian claims, Mengele's notorious experiments may have borne fruit.

For years scientists have failed to discover why as many as one in five pregnancies in a small Brazilian town have resulted in twins – most of them blond haired and blue eyed.

But residents of Candido Godoi now claim that Mengele made repeated visits there in the early 1960s, posing at first as a vet but then offering medical treatment to the women of the town.