1. Short-Term Mating Strategies Why Jerry Springer is so Much Fun

2. Inter-Sexual Differences Once again, we come to minimum investment  Women have greater obligatory investment, so have greater risk in pursuing short-term mating (STM) strategy  Men invest less, so have less to risk

3. Male Benefits Greater number of offspring  Due to greater reproductive variance among males  Achieved through larger number of partners rather than invest in one partner

4. Male Costs STDs “Womanizer” reputation Decreased parental investment Death or injury from jealous husbands, female’s kin Cuckolding by, or loss of, long-term mate (LTM)

5. Adaptive Problems for Males Partner Variety Sexual accessibility of female partners Fertility identification Commitment avoidance

6. Evidence for Male STM (1) Physiological  Sperm competition Behavioural  Incidence of extra-pair copulation  Prostitution seeking

7. Evidence for Male STM (2) Psychological  Desire for partner variety (Coolidge effect)  Desire for early intercourse  Lowered & changed standards Closing time phenomenon  Sexual fantasies

8. Female Benefits Resources** Good or diverse genes (untested) Mate switching** Improved mating skills* Increasing status* Mate manipulation or expulsion Jury still out: field research needed

9. Female Costs Reputation of promiscuity Increased risk of abuse and rape Sole parental responsibilities for offspring  Increased incidence of infanticide Risk loss of LTM STDs

10. Evidence for Female STM Female orgasm  Increased sperm retention  Ovulation & copulation timing in STM Incidence of extra-pair copulations

11. Context Effects Sexual gratification Life transitions Sex ratio Self-perceived mating success & self-esteem

12. Selection of Reproductive Traits HumanChimpanzeeOrangutanGorilla Penis Testes HumanChimpanzeeOrangutanGorilla Breasts

13. The Wrap-Up Minimum investment Costs & benefits for STM Evidence Context effects Selected physiological characteristics

14. Things to Come The Problems of Parenting  Sex differences in parental care  Genetic relatedness Investment Abuse & neglect  Offspring reproductive success  Parent-offspring conflict