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Female Choice

Female Choice. Limiting Resource. Females Finite offspring production Intersexual selection “Female choice”. To Be Considered. Male dominance and status Male resources Paternal investment (Dads vs. Cads). Buss (1989). Cross cultural

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Female Choice

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  1. Female Choice

  2. Limiting Resource • Females • Finite offspring production • Intersexual selection • “Female choice”

  3. To Be Considered • Male dominance and status • Male resources • Paternal investment (Dads vs. Cads)

  4. Buss (1989) • Cross cultural • Women rank current resources, ambition, and dominance (social status) highly • Dominance and resources generally positively correlated

  5. Sadalla et al. (1987) • Silent video of two men interacting in office environment shown to female subjects • More dominant male rated as having higher status and being more attractive • Actual attributes of each male controlled for

  6. Theory • Dominant males should produce more offspring than submissive males • More access to females • Intra- and intersexual competition • Polygyny • Maximize inclusive fitness

  7. Non-humans and Pre-modern Humans • Non-humans: this generalization seems to hold quite well (e.g., Ellis 2002) • Also, for pre-modern humans (e.g., Boone (1986), Borgerhoff Mulder (1990), Voland (1990)) • Problems with application to modern, industrialized human populations • Low socioeconomic classes have more children than upper classes

  8. Dominance • Socioeconomic class may not be a good measure of dominance • Humans evolved in small social groups • Mazur et al. (1984): West Pointers • Graduation photos and rank 20 years later • Dominants didn’t have more children than submissives • Modern contraception

  9. Mazur, Halpern & Udry (1994) • Redirected the question • Do dominant looking males have more opportunity for copulation than submissive males? • In pre-modern period this would likely correlate with higher number of offspring

  10. Method • 3 year longitudinal study • Male students, starting at grade 7 or 8 • Every 6 months • Questionnaire on sexual experience • Assessment of pubertal development • Dominance rating based on school yearbook photo • Attractiveness rating • Self and interviewer ratings

  11. Results • Most sexually active boys are more: • Dominant looking, attractive, pubertally developed • Dominant boys tend to be attractive • Dominant and attractive boys tend not to wear glasses • Dominance is the best predictor of sexual intercourse

  12. What Makes a Dominant Teenage Male? • Dominant faces • Handsome or muscular • Oval or rectangular in shape • Prominent brow and chin • Submissive faces • Round (pudgy) or narrow (skinny) • Less attractive • Have glasses

  13. Implications • Dominance is the best predictor, although attractiveness is also important • No data here on female choice • Are females attracted to dominant males? • Do dominant males make their own opportunities for sexual experience?

  14. Bogaret & Fisher (1995) • Variability in sexual behaviour • Physiological, cultural, behavioural explanations • Between sexes • Within sexes • Often larger than between

  15. Study • Used 9 predictor variables • Age, attractiveness, psychoticism, dominance, social intimacy, male hypermasculinity, testosterone, sensation seeking, sexual affect • Recorded number of lifetime sexual partners and number of partners in one month from 215 male undergraduates • Question: are some of the 9 variables redundant?

  16. Results • Significant positive correlation between number of lifetime sexual partners and: • Positive sexual affect, antisocial tendencies, physical attractiveness, sensation seeking, and testosterone • Age, sensation seeking, and testosterone account for 25-30% of the variation

  17. Townsend, Kline, & Wasserman (1995) • University age males and females with high sexual activity • Males with greatest number of sexual partners were star athletes, fraternity leaders, other high profile positions

  18. Status • Male success depended upon their status being high and being known • E.g., football and basketball stars had greater access to women than rugby and lacrosse, especially when football and basketball on network TV • Male’s best success was with female university students who knew their status • Wear varsity jacket to advertise

  19. Status and Fitness • Across species, link between male status and fitness • Symons (1979) argues females mating with such males will achieve sons that will be equally successful • Success of university athletes in previous study?

  20. Sperm donor Long-term mate Mean Importance Rating Character Health Physical Abilities Heritability 1.93 4.05 4.69 3.36 Scheib (1994) • Hypothetical artificial insemination • Decouples genetic from resource contribution • Hypothetical dating service (for long-term relationship)

  21. Heritability • Physical, health, abilities, then character • Character/personality not believed to be passed by genes • Value in long-term mate understandable, but importance in sperm donor unexpected • Possibility that it is very difficult to decouple psychological mechanisms of long-term choice in sperm donor context

  22. Age & Status • Buss (1989) • Preference for males 3.42 years older • Male RV • Resources • Gangestad & Buss (1993) • Slight negative effect on female preference for physical attractiveness • The more wealth men can acquire, the less important looks are

  23. Age difference (years)Percent -27 0.1 -15 0.1 -12 0.2 -11 0.1 -10 0.4 -9 0.1 -8 0.1 -7 0.3 -6 0.6 -5 1.1 -4 0.6 -3 1.1 -2 2.5 -1 3.7 0 8.0 1 8.4 2 14.1 3 11.5 4 12.3 5 7.6 6 6.7 7 5.1 8 3.4 9 3.3 10 2.4 11 1.5 12 0.8 13 1.2 14 0.6 15 0.1 16 0.4 17 0.5 18 0.1 19 0.1 20 0.5 22 0.1 Bereczkei & Csanaky (1996) 11.4% • Hungarian data set • Couples with older, higher educated husbands and younger, less educated wives had significantly longer marriages Female Mean age age at difference Marriage (years) 17 -5.21 18-20 -4.25 21-23 -3.11 24-28 -2.41 >28 -5.13 Age difference Mean number at marriage of children Younger husband 1.68 No age difference 1.85 Older husband 1.91 - female older; + male older

  24. Hopcroft (2006) • Status and reproductive success • Potential fertility • Reported rates of sex • Achieved fertility • Number of biological children claimed • United States, General Social Surveys (1989-2000)

  25. Results • Income increases frequency of sex for males, but not females • Education decreases potential and achieved fertility for males and females • But, better educated men have more children than better educated women

  26. Conclusions • Income increases male/female differences and education narrows male/female differences re: fertility behaviour • Income, for males, at least may translate to proximate and ultimate reproductive success • Extremes (very poor and very rich) excluded from this study, though

  27. Testosterone • Believed to be immunosuppressant (Kanda et al. 1996) • Handicap principle • Male facial features may be honest signal of genetic fitness

  28. Conflict • High testosterone males • Good genes • Higher number of sexual partners • Low(er) parental investors

  29. Mazur & Michalek (1998) • Measured testosterone in military men • Testosterone levels drop at time of marriage • High testosterone males have less stable marriages

  30. Gray et al. (2004) • Compared testosterone levels in males in different relationships • Single males had higher testosterone levels than those in established relationships • Suggests testosterone drops in long-term relationships to promote pairbonding

  31. Waynforth, Delwadia & Camm (2005) • Facial photos of 45 men • Measures of facial features (e.g., jaw, eyebrow ridge) influenced by testosterone • Women rated photos for attractiveness • Only women interested in short-term relationships (higher sociosexuality scores) showed preference for facial masculinity • Most preferred less testosterone-driven face

  32. Meaning… • Some support for handicap principle • But, handicap interpretation not the only or the most significant factor in female choice • Changing testosterone levels in males given relationship type complicates matter

  33. Boothroyd et al. (2005) • Examined male faces • Female variables • Their own attractiveness, phase of menstrual cycle, in or out of a current relationship • Interestingly, female preferences explainable by maturity cues as opposed to health cues

  34. Multiple Motives Hypothesis • Cunningham, Barbee, & Pike (1990) • Female choice contradictory • Want dominant, high status mature male, but also want socially approachable, nurturing characteristics

  35. Dominant Males • Good defense against other males • Protection of female, mate guarding • High aggression • May be directed at female and/or offspring • More likelihood of promiscuity/polygyny

  36. Four Features • Neonate • E.g., large eyes, small nose area • Mature • E.g., prominent cheekbones, large chin, thick eyebrows • Expressive • E.g., large smile • Grooming • E.g., high status clothing

  37. Ideal Face • Not an average • Extreme neonate and mature features combined to produce most attractive male faces • “Cute” and “rugged” simultaneously • Elicits feelings of nurturance and respect in women

  38. Other Body Attributes • Want dominant, but not too dominant • Various features besides facial representative • Graziano et al. (1978) • Even tall women prefer men of medium as opposed to short, or very tall height • Horvath (1981) • Women prefer moderately-broad to non- or very- broad shoulders • Lavrakas (1975) • Female preference for fit, but not extreme male physique

  39. Female Alternatives • Good genes • Dominant, masculine • “Cads” • Good paternal investment • Willingness to provide resources • “Dads”

  40. Dads • Schmitt & Buss (1996) • Demonstrate helpfulness, honesty, kindness, sensitivity • Good communication skills • Invoke love and show commitment • Display resources and/or show potential for long-term resource stability

  41. Cads • Buss & Schmitt (1993) • Machismo • Provide immediate resources as gifts • Dominance displays • Show-off • Don’t have or won’t invest for long-term

  42. Options • Secure a Dad • Gain resources • May not be best genes • Extrapair copulations (EPCs) • Mate with Cad • High quality genes

  43. Concealed Ovulation • Human females lack obvious signs of estrous, unusual within the primates (Domb & Pagel, 2001) • Most primates (and other mammals) only mate when females are likely to conceive

  44. Theories • Promotes paternal certainty (Alexander & Noonan, 1979) • Male forced to mate guard and mate with a female frequently • Promotes paternal confusion (Hrdy, 1981) • Many males mate with female and any could be father of offspring; reduces infanticide • Reduces risk that self-aware human females will use contraception to avoid risks of pregnancy (Burley, 1979) • Benefits females by allowing for EPCs with higher quality males

  45. Female Reproductive Cycle • Normally ovulating women fertile for 6-7 days each month • Sperm can survive for several days in uterus • Hours after ovulation, conception no longer possible • Females will, however, have sexual intercourse throughout their reproductive cycle (i.e., non-reproductive sex) (Bellis & Baker 1990; Baker & Bellis 1995)

  46. Female Sexual Desire • Continuous receptivity, but changing sexual desire across the cycle • Sexual desire peaks in mid-to-late follicular and periovulatory phases of cycle (Regan 1996; Slob et al. 1996) • With increased sexual interest mid-cycle, might predict increased frequency of female-initiated sexual intercourse at mid-cycle

  47. Female EPCs • Baker & Bellis (1995) • Women with long-term sexual partner • 6% reported last sexual intercourse with extrapair partner • Frequency of EPC was three times more likely to occur at mid-cycle • Gangestad et al. (2001) • Females more likely to fantasize about extrapair partner at mid-cycle

  48. Implication • Females adapted to mate when most likely to conceive • Females in long-term relationships are more likely to engage in EPCs when most likely to conceive • Risk of getting caught? • …Heading off on a bit of a tangent here…

  49. Gangestad & Cousins (2001) • Low FA men rated as attractive only by women interested in casual sex • For long-term relationships, these same women did not find low FA men more attractive • If low FA correlates with higher genetic fitness, offers support for idea of females’ use of traits to identify good gene providers

  50. Low FA Males as Mates • Various studies show that low FA males may make poor long-term mates • Have more female partners, produce more offspring, more dominant, more likely to get into fights, etc. (Waynforth 1998; Gangestad & Thornhill 1997, Furlow et al. 1998) • But, might be very good candidates for short-term mates (i.e., Cads)

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