Long-term mating

What is the bottom line according to Darwin?

-reproduction
-therefore mating is crucial, effortful & complex

How is sex defined & who is the greater investing sex?

-gametes
-greater investing sex is choosier
-women have larger, less mobile reproductive gametes & produce a fixed amount approx 400 ova
-lesser investing sex compete more intensely for mating access

Why has evolution favoured women who were highly selective about their mates?

-greater initial parental investment of females makes them a valuable reproductive resource so don't just give them away
-risked investing enormously as a consequence of having sex
-modern technology has changed this; women can now have ST sexual encounte

what gender has the most reproductive variance?

-males
-low PI sex

Sexual selection involves what 2 processes?

-intersexual selection (choice; females choose males)
-intrasexual competition
-adaptations designed for both that may not be designed for survival but gain access to females & resources

What happens when males are the higher-investing sex?

-females tend to be more competitive & less choosy

What types of mating systems are there?

-ST
-LT; monogamy, polygamy (1 male, 2 females), polygyny (1 female, 2 males)

How can a species mating system influence its adaptations?

-beta males may try to compete for females surrounded by the alpha male
-can be characterised by physical & anthropometic cues as well as anthropological evidence; e.g. men are larger than women over evolutionary history to better compete for resources, c

People are flexibile strategists so..

-no natural strategy; no one mating system consistent with human nature
-best strategy depends on circumstances.

What circumstances affect mating strategy?

-mate value
-life expectancy
-environmental conditions (e.g. environmental harshness; need for biparental care)
-cultural norms + taboos
-male-female sex ratio

What do humans typically do (especially females)?

-trade-offs that people make in mating strategies
-females choosing 'good genes' males vs 'good providers'
-choose latter when male PI is more crucial

What does sociosexuality measure?

-individual interest in STM

What was originally thought about sociosexuality?

-1-dimensional construct; opposite of interest in LTM
-but now these 2 strategies arent negatively correlated as one might expect especially in males

Where is sociosexuality higher?

nations w/ more 'men' & less 'hardship'
-cross-culturally, men have higher mean sociosexuality
-although most societies allow polygyny, most relationships are monogamous, 83% polygynous, 16% monogamous, <1% polyandrous

Difference b/w men & women in terms of investment

-differ greatly in the obligatory investment, actual PI usually turns out to be equal
-men are much more higher investing than males of most mammalian/primate species

Why do men contribute more than the minimum PI?

-it is important to offspring survival in EEA; however this varys more than female PI
-compromise w/ female interest; men who fail to commit might have failed to attract women at all as women may require reliable signs of commitment before consenting to s

What has male PI helped with?

-securing food/territory
-builds shelter/tools
-physically defend against enemies
-rear children
-acquire social support via kin, alliances, social status
-voice family interests in social/political sphere

What is most important to mothers?

-receiving PI in forms of material resources more important to mothers than fathers
-therefore women place greater emphasis on economic resources of mate
-very robust finding cross-culturally (females rank it on average 2x as high as males)

When does preference for economic resources of a mate increase?

-in females who are more independently wealthy
-in a cross-cultural study, all women placed more value than men on good financial prospects (despite differences)
-variability in the extent of sex differences & in strength of preference but always more imp

What is the case in H-G societies?

-no money so preference is for other forms of 'material wealth' (e.g. access to meat, difficult-to-acquire resources)
-costly signals
-men attract women by advertising their ability to access resources

Preferences for men w/ higher social status

-robust cultural differences
-EEA-like societies are described as more egalitarian however status differences still exist & are associated w/ access to wives & resources
-women desire men who command a high position because social status is a universal cu

Preferences for older men

-in all 37 cultures, women prefer men who are older by 2-5 years
-this is due to change that comes w/ age; e.g. more access to resources, higher status, expertise, physical strength

Is this status trend for older men limited to the western world?

-no
-In Trini (polygynous people) men are typically at least 30 before they have enough social status to acquire a 1st wife

However what is the cut-off point for older men?

-women in their 20s dont really want a mate who is substantially older even though their resources dont peak until 40s or 50s
-this is because there is a risk of them dying & hence less likely to be around to continue contributing to the provisioning & pr

Preference for ambitiousness & industriousness?

-those who work hard achieve higher levels of education, higher annual salaries; US women are aware of this connection
-women in the study of ST & LTM regard men who lack ambition as undesirable; likely to discontinue a relationship if he loses his job, l

Preference for athletic prowess

-correlated w/ ability to hunt, defend, fight, produce, build etc
-tend to prefer tall men, v-shaped torso, shoulder-hip ratio
-women judged short men to be undesirable for either a ST or permanent mate
-80% want a male to be 6ft or taller (Cameron et al

Is the preference for athletic prowess limited to western culture/

-during evolutionary history, physical protection was one of the most important things a man could offer a woman
-however women dont want a man that is too muscular;
-in studies, waist-chest ratio is the best predictor of male bodily attractiveness

What about faces/

-preference for more healthy, masculine (somewhat ambiguous findings), & symmetrical
-men tend to have larger + broader jaws, stronger, brow ridges & more pronounced cheekbones due to testosterone

Why are these preferences for faces found?

-men w/ more symmetrical faces experienced fewer respiratory illnesses suggesting better disease resistance but this association is not yet convincing

What else is important besides ability to invest?

-willingness to invest
-love & commitment v.important in both sexes
-women are sensitive to cues that potential mate interacts well w/ children (men are not)

What additional preferences do women have?

-humour
-deep voice
-avoiding incest
-compatibility inc. values, intelligence, personality; equally important to men
-kindness, dependability; equally important to men

Condition-dependent factors (good genes hypothesis)

-increases preferences for masculine faces
-women become more demanding in preferences when own mate value is higher
-'good genes hypothesis' - when women are more likely to get pregnant, they are especially attracted to men whose faces have been scored b

What cues are more important in LTM context?

-cues related to male PI vs good genes
-kindness more important in LTM; looks more important in STM

What are men's chief adaptive problems (LTM strategies)?

-involve monopolizing reproductive potential of high reproductive value women

What is reproductive value?

-# of children a person is likely to have in the future (takes mortality into account)
-for women this peaks in teens & declines steadily until menopause; fertility peaks in mid-20s

Men's preference for youth...

-it is a critical cue because a women's reproductive value declines steadily as she moves past age 20
-not confined to the western world
-men in 20s + older universally prefer younger women

How do men's preference for youth vary?

-some cross-cultural variation (e.g. preferred age gap greater in polygynous societies, lower in Scandinavia)
-gap gets larger as men get older (men in 30s prefer 5yr age gap, men in 50s prefer 10-20 yr age gap)

What do teen boys prefer?

-a woman who is a few years older than them (for them, older women are at peak fertility)

What are some physical cues to youth & health?

-clear, smooth, unblemished skin signals youth & absence of disease/parasites
-facial symmetry
-facial averageness
-facial femininity (smaller chin/jaw, larger eyes, fuller lips; linked to youth & oestrogen/fertility)

Are there standards of beauty?

-probably reside in adaptations of behold
-emerges in 3-8 month old infants
-highly consistent standards across cultures

What cues vary cross-culturally in regards to standards of beauty?

-body fat which may relate to food availabilty
-lower female WHR is a cue to both health & fertility

What is the standard of beauty in cultures where food is scarce?

-E.g. bushmen in Australia
-plumpness signals wealth, health & adequate nutrition during development
-in ecologies where food shortages are common, such as Kenya, men prefer women who are heavier & possess more body fat

How is this standard of beauty reversed in countries where food is relatively abundant?

-wealthy distinguish themself by being thin

What remains constant?

-although preference for body fat changes. preference for lower WHR is more constant
-0.70 is optimal

Why might WHR remain constant?

-related to child intelligence
-maybe because hip fat contains long-chain fatty acids, critical for foetal brain development

However why might the case of WHR be overstated?

-replicated cross-culturally but seems calibrated to local population mean WHR
-some studies suggest that other factors are more important, especially body size relevant to height (e.g. BMI)
-links to fertility & health are not unequivocal

What about preference for attractiveness?

-in all 37 cultures, men valued looks in a mate more than women did
-both men & women emphasise looks alot more than in 1939
-this may be due to influence of mass media artifically inflating our expectations
-when men see images of beautiful women, they e

What cues do men respond to for ovulation

-unlike other primates human females have concealed oestrus
-vascularisation & lightening of skin; more attractive face
-reduced WHR (due to estrogen)
-increased touching
-more pleasant odour
-increased female sexual desire

How do men control for certainty of paternity?

-often are quite jealous
-value faithfulness more; many cultures restrict displays of female sexuality, probably as a way to promote paternity uncertanity
-extent of restriction varies widely
-valuation of premartial chastity varies widely cross-culturall

What do men rank highest in LTM contexts?

-faithfulness & loyalty out of 67 traits
-cross-culturally, unfaithfulness is the least desirable LTM characteristic for men

Do women also rank unfaithfulness high?

-they do but not as much as men
-reproductive consequences of being cheated on are bad for both but tend to be worse for men

How does status affect behaviour?

-high-powered men tend to have more attractive & younger mates

Tradeoff b/w mating, parenting?

-testosterone helps w/ mating, less so w/ r.ships + parenting
-drops post-marriage, again post-offspring

what does the 'good gene' selection theory say?

-individuals have evolved preferences for traits that may increase the likelihood of reproductive success w/ a viable mate (Rhodes, 2006)

What traits are deemed more attractive?

-Barber (1995)
-large chins, prominent cheekbones, square jaws, thick eyebrows
-small eyes & thin lips

What did Koscinksi (2007) claim?

-these traits may reflect an important adaptation that served our ancestors
-e.g. protruding brow ridges w/ bushy eyebrowns set close to the eyes may have provided an effective method in protecting the eyes from the sun as well as prohibiting sweat from g

Why do women pick these traits?

-could be due to a lack of illness during development as well as a signal to current physical health (Geary et al, 2004)
-result of testosterone which suppresses the immune system so if men have these traits it shows good genetic quality which enhances re