According to a new study, lap dancers who menstruate regularly and are in their most fertile periods receive better tips than dancers who are taking the hormonal contraceptive pill. According to University of New Mexico, Albuquerque psychology professor Geoffrey Miller and his colleagues, this research provides more evidence that women go "into heat," hormone-induced estrus, like other female mammals. From New Scientist:
But the study does appear to show that the dancers somehow advertise their fertility to men, who then consider them more attractive during this fertile phase, as reflected in their tips. How they advertise, however, and whether they do it consciously, is unclear. "We don't know the mechanism of attraction," says Thornhill, who is also at the University of New Mexico but was not involved with the study. "Are the men detecting the scent of oestrus? Or does the women's behaviour change?" he asks.
Link to New Scientist, Link to more info at Mind Hacks, Link to scientific paper abstract in the journal Evolution And Human Behavior