Claus Wedekind

Claus Wedekind is a Swiss biological researcher notable for his 1995 study that determined a major histocompatibility complex (MHC) dependent mate preference in humans.

This study is often known as the "sweaty T-shirt study". In it, men each wore the same T-shirt for two days. The shirts were then put into identical boxes. Various women were asked to smell the shirts, and to indicate to which shirts they were most sexually attracted. The results showed that women were most attracted to men with an MHC most dissimilar from their own. Provided by Wikipedia