OppoScents Attract!

A bizarre 1995 experiment conducted by Claus Wedekind and colleagues at the University of Bern in Switzerland asked female students to sniff T-shirts that had been worn for three days by male volunteers and rate them for attractiveness. The DNA of the men and the women was then analyzed, in particular the genes, which build a part of the immune system. The infamous Stinky T-Shirt Study showed that women were biologically programmed to sniff out men with immune systems vastly different from their own, thus creating a wider gene pool and more robust offspring. Interestingly, this preference was reversed in women who were taking oral contraceptives (which mimic pregnancy). Women on the pill preferred the scent of men with very similar genetics, such as close relatives, who would be more likely to help her care for the baby.