3. SOURCES OF EVIDENCE 1. Universality 2. Unique predictions

4.  sex differences in reproductive behavior are universal  Implies that they are built into the genetic code of our species  E.g. mating style differences (Clark & Hatfield study)

6.  Only EP makes certain predictions about sex differences  No prediction from other psychological theories

7.  Class survey  “I HAVE BAD NEWS”  Which is worse ?

8. -studies of personal ads Men – ask for younger Women – ask for older

9.  Men tend to agree with each other and are not influenced by other factors  Women’s judgments of attractiveness are influenced by other features (eg a man’s personality, wealth)

10. Fact: Women say they want nice guys Q: Do they really?

11.  In the pretest, women subjects said that their main criterion for a partner was “a nice guy”  Then they were asked to observe videos of men in discussion groups  They rated the attractiveness of a certain guy Kenrick’s Videotape Study

12. Dominant & nastyDominant & nice Submissive & nastySubmissive & nice

13.  Dominant men were rated as more attractive  Niceness did not make a difference  BUT -- depends on expected length of relationship (one date vs. lifetime relationship)

15.  Why would it be important?  EP predicts that males should care a lot

16. Took photos of subjects Morphed some of them into baby pictures

17.  STEP 1  Took photos of student subjects  Morphed some of them into baby pictures

19.  Brought the same subjects back to rate baby pictures  One picture is a morph of the subject & baby face  Subjects were asked to rate:  Which baby is more attractive ?  Which baby would you adopt ?  Which baby would you spend money on ?

20.  MALES  Showed strong preference for child resembling them  FEMALES  Showed no preference by resemblance

21.  T.V. remote?  Bath or shower?  Shoes?

23. 1. PARENTAL INVESTMENT The sex that contributes more to raising offspring – is more discriminating in sexual mate choice.

24.  Females are more certain that a baby is theirs  But Males are not sure and so have to be more concerned  They need to avoid wasting their resources on unrelated offspring  e.g. Maury Povich T.V. show

25. !!

26.  Unique form of emotional attachment to sexual partners  Adaptive for sustaining the relationship  Otherwise the offspring won’t survive

28.  Parental investment  sex vs. relationship focus  casual sex  age preferences  Parental certainty  Jealousy  Self-similarity of baby  Pair-bonding  attachment & love