Interaction Between the Sexes By: Jesse Brownstein, Johnathan Lou, and Blake Williamson

What is estrus and does it exist? –Estrus is a phase of increased female sexual receptivity, attractiveness, and selectivity –Thought to be lost over evolution Not really real world economic evidence researching estrus If estrus did exist, men would be more attracted to women based on scent, facial attractiveness, increased soft-tissue symmetry and verbal creativity and fluency. Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28,

18 women participants (11 of which on pill) were recruited through indirect s Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28, Asked to log moods, work hours, location, and tip earning on website Also asked to log 60 days of menstrual cycle Each participant’s menstruation data was plotted on a calendar which showed how many days into the cycle of each participant was for each shift reported

The average tip-earning was calculated for each level of each participant’s menstrual, fertile, and luteal phases Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28, All 18 participants showed regular cycles (28 to 29 days) Reported mean earnings was $ per shift with each lap dance earning roughly $14 ($250 reflects about 18 dances per shift). The normally cycling women made a lot more money during estrus than during the luteal or menstrual phase - ($354 per shift during estrus - about $90 more than during the luteal phase and about $170 more than during the menstrual phase

Estrus women made about $70 per hour Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28, Luteal women made about $50 per hour Menstruating women made about $35 per hour Pill users made only $193 per shift compared to normally cycling women making $276 per shift.

1. "leaked" or deliberate signals? Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28, disenfranchised males' lucky day 3. rules of attraction

1. Method Design - Reporting issues (only 27% of days logged) - Small sample size (n= 18) - Limited demographics (Albuquerque, Anglo and Hispanic males) Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28, Analysis - Contraceptives & "Off the record" income - Inaccurate menstrual cycle measures

of-sex-appeal-female-flirtation.htmlhttp://dsc.discovery.com/videos/science- of-sex-appeal-female-flirtation.html Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28,

True/False 1.Estrus is a phase of increased female sexual receptivity, proceptivity, selectivity, and attractiveness. (T) 2. Women are near the most fertile point of their cycle just after ovulation. (F) 3. According to the article, participants that took pill-contraceptives did not have mid-cycle peak in tip-earnings. (T) Miller, G., Tybur, J., & Jordan, B. (2007). Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus. Evolution and Human Behavior, 28,