Mating and Attractiveness.

Question 1

Who introduced the theoretic foundation of the theory of parental investment (PI) and sexual selection?

Answer 1

Trivers’ 1972

Question 2

Sexual selection involves two main processes:

Answer 2

• Intersexual selection (choice).

- Intrasexual competition.

Question 3

Adaptations designed by intersexual selection (animals).

Answer 3

• male peacock, mandril. - designed to appeal to females. - can impede survival - carrying around huge tail.
• Hermit crabs, male deer antlers. - naturalised weaponry, protection, competition. - can impede survival, carrying around antlers, and can get stuck in trees.

Question 4

Exceptions (that prove the rule):

Answer 4

In species where males have higher PI (e.g. seahorses, phalaropes), females tend to be more competitive and less choosy, and to have more mates.

Question 5

What does a decline in human sexual dimorphism over course of evolution suggest?

Answer 5

Suggesting a trend towards increased biparental care, vibrant monogamy.

Question 6

Sperm Competition.

Answer 6

• Chimps, of all the primates, have the largest testes to body size.
• Due to their promiscuous breeding system, some male chimps have large testes, providing an advantage.
• It is an advantage because they have more sperm production because as the female chimps have multiple male partners, and will have the sperm of multiple males inside her reproductive tract, there will be competition within the reproductive tract
• Gorillas have a small testes to body ratio - they do not need such large testes because the females aren’t mating with other males, meaning there is less competition and you won’t need to produce as much sperm.

Question 7

Humans are flexible strategists…

Answer 7

so all strategies are all equally ‘natural’.

Everything is natural.

Question 8

What circumstances does the best strategy depend on?

Answer 8

• Individual characteristics like mate value, life expectancy.
• Environmental factors like harshness of environment (need for bi-parental care) - - - male-female sex ratio.
• human legal environment (in most Western industrialised cultures, polygamy is illegal).

Question 9

Flexible strategizing & strategic pluralism:

Answer 9

• Trade-offs that mating strategies entail, e.g. females choosing ‘good genes’ male versus ‘good provider’.
• Choose good provider when male parental investment (i.e., bi-parental care) is more crucial. - when it’s a harsh env, bi-parental care is important.

Question 10

What does ‘Sociosexuality’ (or ‘sociosexual orientation’) measure?

Answer 10

individual interest in short-term mating.

- individual difference in the willingness to engage in sexual activity outside of a committed relationship

Question 11

Where, what and who has higher socio-sexuality? (Schmitt, 2005).

Answer 11

• higher in nations with fewer men and less ‘hardship’,

- cross-culturally, men have higher mean socio-sexuality.

Question 12

Important socio-sexuality findings -

Answer 12

• when life is harder, that is when two parents are going to come together and consistently invest.
• If there are signs of hardship, such as mortality, child malnutrition, these will be negatively correlated, and people will be less enthusiastic about having short-term relationships with multiple partners, and more focused on bi-parental care and monogamy.
• If there are positive indicators, such as living in a wealthy country, you’re going to have a higher sense of sexuality, easier access to resources and provide for your offspring with health care.

Question 13

What happens if there are more males there are than females in terms of socio-sexuality?

Answer 13

the more female-like the dominant mating system becomes. (long-term, bi-parental).

• females become more =in demand’ and valuable.
• Schmitt - cross-nationally, male AND female SOI was higher when male to fem sex ratio is lower

Question 14

What are three theories Buss mentions (in order of empirical support).

Answer 14

1. Female fertility (genetic theory), as explanation for homosexuality in males and females.
2. kin altruism
3. alliance formation

Question 15

Female fertility (genetic theory), as explanation for homosexuality in males and females -

Answer 15

• Idea is that there is a gene that increases female sexuality and sexual desire towards males, same thing in males, which eroticises the same sex (males).
• The benefit for female reproduction is so great that it offsets the cost of having this gene present in males.
• If these genes are present in one sex and have a negative effect on reproduction, they may compensate for that by having a positive effect on the other sex.

Question 16

Kin altruism

Answer 16

• Homosexual are more likely to remain ‘helpers of the nest’.
• Will invest more in the offspring of close kin, which via kin selection could lead to the genes for homosexuality.

Question 17

Alliance formation

Answer 17

• The idea that homosexuality is used as a way to still have fine alliances in some cultures.
• You see this in bonobo chimps - seems to be a way of bonding - not necessarily as sexual partners.

Question 18

female orgasm, as a by-product.

Answer 18

• This analysis is specially designed to solve a specific kind of adaptive problem.
• He believed it is a by-product, that the female orgasm is a bi-product of the male orgasm.
• Because the male orgasm is motivating the male to achieve orgasm, which is ejaculation, needed for reproduction.
• Why would you need to instil that motivation in the female? - because it is not necessary for reproduction.

Question 19

How did men’s PI help in EEA societies?

Answer 19

Secure food, territory.
Build shelters, tools.
Physically defend against enemies/predators.
Acquire social support (e.g. shared food, medical help) via kin, alliances, social status.
Rear children (instruction, discipline).
Voice family’s interest in the social/political sphere.

Question 20

Receiving PI in the form of material resources are more important to mothers than to fathers.

Answer 20

• women place greater emphasis on the economic resources of mates.
  ‘Robust finding in a vast variety of cultures’ (ability to procure and retain resources) - females rank it on average twice as high as males.
• This preference increases in females who are more independently wealthy.

Question 21

Women’s preferences in men -

Answer 21

• receiving pi in form of material resources
• high social status
• willingness to invest
• Older men
• dependability and stability
• athletic

Question 22

Preference for men of high social status.

Answer 22

Again, this is a robust cross-cultural difference.
EEA-like societies are sometimes described as ‘egalitarian’, and indeed are in many ways.
However, status differences exist and are associated with access to resources and wives.

Question 23

Older men

Answer 23

In all 37 cultures (Buss, 1989), women tended to prefer older men, though not too much older (mean of 3.5 years older, range about 2-5 years).
Older men have higher status, more resources, and expertise.
But if too old, it raises issues of survival and health.

Question 24

ability to invest, willingness to invest

Answer 24

Women are sensitive to cues that a potential mate interacts well with children (men are not; La Cerra, 1994)

Question 25

Women prefer athletic prowess

Answer 25

(correlated with ability to hunt, fight, defend, produce, build, etc).
Tend to prefer taller men, V-shaped torso (waist-chest ratio, shoulder hip ratio).

In studies, waist-chest ratio is the best predictor of male bodily attractiveness. (Price, et al, 2013).
Women also prefer faces that appear more healthy, symmetrical, average.

Question 26

What is Condition dependence?

Answer 26

Phenomenon where your preferences depend on your own physical condition.

• Ovulation may increase preference for masculine faces, bodily symmetry
• Women become more demanding in preferences when their own mate value is higher (Penton Voak et al., 2000).

Question 27

Trade offs for looks vs character in LTM vs STM contexts:

Answer 27

• Cues related to male parental investment vs good genes are more important in LTM context.
• E.g. kindness more important in LTM; looks more important in STM.

Question 28

reproductive value (RV)

Answer 28

number of children a person is likely to have in the future (takes morality into account).

Question 29

Men’s LTM strategies:

Answer 29

• youthfulness, Men in their 20s and older universally prefer younger women (Buss, 1989) - assessed by clear skin, facial symmetry averageness and femininity (linked to youth and oestrogen/fertility)
• Lower waist-hip ratio (cue to health and fertility).
• In all 37 cultures, men valued looks in a mate more than women did. - due to mass media and expectation?

Question 30

Females (human) have concealed oestrous - what Cues to ovulation that men may detect and/or respond to?

Answer 30

• Vascularisation and lightening of skin; more attractive face.
• Reduced WHR (due to oestrogen).
• Increased touching.
• More pleasant odour.
• Increased female sexual desire.

Question 31

Certainty of paternity is a major problem for men (only)

Answer 31

Jealousy is one solution.
Men cannot always be 100% certain of being the biological father.
Another solution: valuation of cues to faithfulness.
Many cultures restrict “displays of female sexuality” (more than men’s), probably as a way to:
Promote paternity certainty (may benefit men or women).
Reduce female-female competition.

Question 32

‘extra-pair copulation’ (EPC)

Answer 32

• BIRDS
• The female bird will have one long-term male partner, but will be engaging in sex with other males on the side. - getting best genes and best provider simultaneously.

Question 33

Coolidge effect

Answer 33

Effect where males are more aroused by sexual novelty

Question 34

Clark & Hatfield (1989) had male and female confederates approach members of the opposite sex and ask them to:
Go on a date that night,
Go back to their apartment that night, or
Go to bed with them that night.

Answer 34

• Men are willing to have sex a lot sooner.

- Men desire more partners.

Question 35

Strategic variation within men:

Answer 35

• Men with higher mate value (higher attractiveness, status, resources, good genes) are more likely to use short-term mating tactics, because they are more likely to succeed with them.

Question 36

Sexual regret -

Answer 36

Men are more likely to regret missed opportunities for STM; women are more likely to regret engaging in STM.

Question 37

Women’s regret is consistent with what idea?

Answer 37

• STM did not lead to their desired outcome.
• STM can lead to LTM, and women often engage in STM with LTM in mind
• Even with STM, women prefer men who are not in committed relationships and not promiscuous; men don’t care about these things in STM

Question 38

On average (Across indivs and env’s), men have more to gain from mating with multiple partners; why?

Answer 38

Desire more partners (i.e. higher sociosexuality).
Willing to have sex sooner.
Willing to lower standards more.
More receptive to offers of sex from strangers.
More aroused by novelty.
More aroused by visual stimuli alone (porn).
More likely to employ prostitutes.