The prize in economics
went to Geoffrey Miller, Joshua Tybur, and Brent Jordan of the University of New Mexico, who had discovered that lap dancers' tip earnings rise and fall with their ovulatory cycles—from an average of U.S. $70 per hour when about to ovulate to just $35 during menstruation.
Previous studies had shown that women in mid-cycle have faces and breasts that are more attractive to men, as well as a more appealing scent, Miller said.
Research also suggests that many women are happier at this time.
"Men are probably responding partly to physical appearance and smell, and quite a bit to behavior, happiness, and outgoingness—but we really don't know yet," Miller said.