Buss (1989)

Study 9

Mate preferencesYou have to marry one of these people. Who and why? (they are all actors)

Evolutionary recap

Bennett-Levy and Marteau = evolution of phobias for survival

Buss = evolution of mating preferences for reproduction

What behaviour would lead to increased/ decreased success at reproduction?

1. Context

If humans have evolved, characteristics that increase the success of reproduction should appear more often in the population

Thornhill and Thornhill (1983)

People lacking these characteristics will not be able to mate and to become people’s ancestors

1. ContextCurrent mate preference is of interest to evolutionary psychologists as it tells us about past reproductive history.

Mate preference is important, but little is known about the characteristics which are valued by males and females.

Context

3 theories about mate selection

One theory each

Have to explain in a stickman poster

No more than 10 words

1. Context

1. Prediction based on parental investment (Trivers, 1972)

Who invests the most time, energy and resources in raising children?

Female investment is huge, while male investment is minimal

1. Context

1. Prediction based on parental investment

Prediction: women will look for men who can offer resources and protection for both her and her future children

In modern times, this might not be food and shelter, as much as money and status.

1. Context2. Prediction based on reproductive value (Symons, 1979) and fertility (Williams 1975)

Fertility: probability of reproducing now

Reproductive value: probability of reproducing in the future

35 year old vs 10year old

Male vs female

What age would the ideal mate be?

1. Context2. Prediction based on reproductive value and fertility

Youthfulness is a sign of both fertility and reproductive value: good skin, muscle tone full lips and healthy hair

Prediction: as female fertility is related to age, we would predict that men show a preference for younger women. Preference less pronounced in women.

1. Context

3. Prediction based on paternity probability (Daly et al, 1982)

How certain can a woman be that any child she has is hers?

How certain can a man be that his mate’s child is his?

Males want to be certain that they are investing time and resources into their own offspring.

1. Context

Prediction based on paternity probability

Prediction: males should show a greater preference for women who are chaste (i.e. virgins)

As women know that any child they have is theirs, this will be less important

However, males with other partners might have to share resources...

1. Aim

To investigate if evolutionary explanations for sex differences in human mate preferences are found cross culturally

Why use cross cultural studies for evolutionary theories?

2. Procedure

Buss used a questionnaire which assessed preferences for particular traits in potential mates

Using pg 117 in the book, find out the missing information about the participants

Identify the sampling techniques used

2. Procedures

Instrument 1: Rating

What issues did you find with the first questionnaire?

Why not just ask about the four critical factors?

2. Procedures

Instrument 2: Ranking

Putting 13 characteristics in rank order

What problems are there with ranking?

2. Procedures

Translations

Translated into local languages

Avoiding of gender specific terms

Adapted to fit customs

Co-habiting in Sweden

Polygyny in Nigeria

Is this a strength or a weakness?

3. FindingsSignificance recap: If it is “significant” there is less than a 5% probability that it is due to chance

Financial prospects: in 36/37 samples women valued “good financial prospects” higher than men.

Large variation between and within cultures in importance. High value in Africa, Asia and America. Lower in Europe

3. Findings

Ambition and industriousness

In 34/37 samples females desired ambition higher than males

3/37 males had a higher preference in women

In these cultures, women carry out many physical tasks

Not rated low in any sample, although UK, Germany, Netherlands and Finland showed less preference

3. Findings

Age Difference

In every sample, men preferred younger women (2.66 years)

Mean age men want to marry: 27.49 years. Therefore ideal age for females to be is 24.83

This is closer to peak fertility rather than peak reproductive value

3. FindingsAge differences

Females preferred older men (3.42 years)

Mean age females want to marry: 25.39 years. Therefore ideal age for males to be is 28.81

Where polygyny is common, desired age difference for men is bigger

In these cultures, men are older when they marry

3. FindingsGood Looks

In all samples, men rated good looks as more important than women

Chastity

Large variation in the importance of chastity

In 23/37 males valued chastity as higher than females.

Important in China, India, Indonesia, Iran Taiwan and Palestine

Seen as irrelevant in most European samples

3. Findings

3. ConclusionsThere are five conclusions in this study. Each one relates to one of the three theories from the context.

Read the conclusions and match to the theory (use the psychologists names)

3. ConclusionsHow do Buss’s findings support the general notion of mating behaviour being innate?

Traits are universal. If they were all different, we could argue it is due to culture. But as they are the same everywhere, is suggests a biological basis for behaviour. Also, the behaviour shown matches what we would predict from evolutionary theory.

3. ConclusionsMating behaviour differs by gender. This reflects the differences in the reproductive capacities of males and females.

Unlike animals, human mate preference is not simply about female choosiness. Males and females both express preferences.

However, Buss also highlighted that there are cultural influences as well. This is demonstrated by the large differences in preferences for chastity between cultures.

…found on the internetDoes this fit with Buss’s findings?

5. Alternative EvidenceBuss found that physical attractiveness was rated highly by nearly all male samples. But why?

What is “attractiveness”? Is it the same in all cultures?

Why… Not…

5. Alternative Evidence

Native Asians and Hispanic students and white Americans rated attractiveness of Asian, Hispanic, black and white women.

Mean correlation between groups in attractiveness ratings was +0.93.

Cunningham et al (1995): close agreement across cultures in female physical attractiveness.

5. Alternative EvidenceWhich woman is most attractive?

5. Alternative EvidenceSingh (1993): waist to hip ration (WHR) related to physical attractiveness across cultures.

Men prefer women who have a low WHR.

A woman with this WHR is likely to have a large bottom (good fat reserves for pregnancy) and a narrow waist (indicating that she is not pregnant)

Low WHR would is attractive because it is a sign of youthfulness and fertility.

5. Alternative EvidenceWhich face is more attractive?

5. Alternative EvidenceWhich face is more attractive?

5. Alternative EvidenceWhich face is more attractive?

5. Alternative Evidence

Little et al (2007) examined preferences for symmetry in both the UK and the Hadza, a primitive hunter gatherer society in Tanzania.

Both groups preferred symmetrical faces, and this was the strongest in the Hadza.

Facial symmetry may be a sign of genetic strength. Therefore, symmetrical faces may be more attractive.

5. Alternative EvidenceSchmitt (2003)

16,288 people from 53 countries

Found universal differences between Male and Female mate choice.

Found in ALL countries men desired a larger number of mates than women did.

What does this suggest about Buss’s conclusions?

5. Alternative EvidenceHow much do people's stated preferences actually reflect their choices?

Waynforth and Dunbar (1995) content analysis of 900 lonely hearts ads, and noted differences in what men and women want.

More men than women sought a youthful mate

More men sought a physically attractive mate

More women used physically attractive terms to describe themselves

More men reported their economic status/earning power when describing themselves.

5. Alternative EvidenceBuss focused on heterosexual relationships. Can we apply to homosexual relationships?

Dunbar (1995) looked at gay personal ads,

Heterosexual women were three times more likely to seek resources and status then lesbians,

Gay men offered resources about half as often as heterosexual men.

This supports the evolutionary explanation; we would not expect lesbian and gay mate choice to be related to reproductive criteria.

5. Alternative EvidenceDunbar also notes that times have changed,

Women have their own economic security, are less interested in a partner’s resources.

Seek instead a caring, sharing partner instead

This still makes evolutionary sense because that kind of partner should still enhance reproductive success.

Use three colours to highlight research that supports, contradicts, or develops Buss’s research