ECONOMICS PRIZE. Geoffrey Miller, Joshua Tybur and Brent Jordan of the University of New Mexico, USA, for discovering that a professional lap dancer's ovulatory cycle affects her tip earnings.
REFERENCE: "Ovulatory Cycle Effects on Tip Earnings by Lap Dancers: Economic Evidence for Human Estrus?" Geoffrey Miller, Joshua M. Tybur, Brent D. Jordan, Evolution and Human Behavior, vol. 28, 2007, pp. 375-81.

Abstract:
To see whether estrus was really “lost” during human evolution (as researchers often claim), we examined ovulatory cycle effects on
tip earnings by professional lap dancers working in gentlemen's clubs. Eighteen dancers recorded their menstrual periods, work shifts, and
tip earnings for 60 days on a study web site. A mixed-model analysis of 296 work shifts (representing about 5300 lap dances) showed an
interaction between cycle phase and hormonal contraception use. Normally cycling participants earned about US$335 per 5-h shift during
estrus, US$260 per shift during the luteal phase, and US$185 per shift during menstruation. By contrast, participants using contraceptive
pills showed no estrous earnings peak. These results constitute the first direct economic evidence for the existence and importance of
estrus in contemporary human females, in a real-world work setting. These results have clear implications for human evolution, sexuality,
and economics.
http://www.unm.edu/~gfmiller/cycle_effects_on_tips.pdf

Go science!