Josef Mengele was a doctor who performed scientific experiments on concentration camp prisoners during World War II.

After the war he fled to South America to avoid trial for war crimes. While living there, he provided medical services to women in the village of Candido Godoi in Brazil. The high percentage of twins found in the town have sparked rumors that Mengele continued his medical experiments in Brazil.Telegraph: Nazi Angel of Death...'Created Twin Town...' (Jan. 21, 2009)

In addition to his human experiments, Menegle supervised the arrival of people at Auschwitz-Birkenau. In this capacity, he determined who would be assigned to the work camp, and who would be sent to the gas chamber.More or Less: Josef Mengele Estimates of the number of people he sent directly to death range as high as 400,000. Daily Star: Nazi Doc’s Secret Master Race (January 23, 2009)

One of Mengele's research projects at Auschwitz was to determine how to produce a twin pregnancy. The Nazis intended to use the results of his research to increase the Aryan birth rate. Historian Jorge Camarasa maintains that the town of Candido Godoi's unusually high percentage of twin pregnancies (one in five pregnancies results in twins) might be due to Mengele, who provided medical services to the town's women in the 1960's.Telegraph: Nazi Angel of Death Josef Mengele 'created Twin Town in Brazil' (January 21, 2009)

Others dispute this theory, maintaining that the high percentage of twins, who are also generally blonde and blue-eyed, is due to an inherited genetic trait that favors twin pregnancies. Guy Walters explains, "Most probable is that they are in some way related to the German immigrants who have populated this part of South America since the 19th century."Mail Online: ...Twins the 'Angel of Death's' Secret Tribe? Not Likely... (Jan. 23, 2009)

"I think Candido Godoi may have been Mengele's laboratory, where he finally managed to fulfill his dreams of creating a master race of blond haired, blue eyed Aryans...There is testimony that he attended women, followed their pregnancies, treated them with new types of drugs and preparations, that he talked of artificial insemination in human beings, and that he continued working with animals, proclaiming that he was capable of getting cows to produce male twins."—Jorge CamarasaTelegraph: Nazi Angel of Death Josef Mengele 'created Twin Town in Brazil' (January 21, 2009)

"Within a relatively small and isolated gene pool, it would not be uncommon to see the genetic predisposition for twins to flourish through the generations."—Guy WaltersMail Online: Are These Twins the 'Angel of Death's' Secret Tribe? Not Likely... (Jan. 23, 2009)