Human Mating Strategies. Some relevant facts: 1. Female investment in offspring – very high Male...

Human Mating Strategies

Some relevant facts:

1. Female investment in offspring – very high

Male investment in offspring – variable

2. Reproductive life

10 20 30 40 50 60 70 80

Female

Male

1. Can humans be shown to mate in a manner consistent with the hypotheses surrounding mate choice by either perception of genetic quality or of ability to provide resources?

Central Question

What should males look for in a mate?

Indicators of fertility (age [youth], health)

What should females look for in a mate?

Indicators of ability to provide resources (age, wealth)

Hypothesis

Women value earning potential more than men

Women value ambition and industriousness more than

men

Men value physical attributes more than women

Men value chastity more than women

Men prefer women younger than themselves

Proportion of cultures supporting hypothesis

0 25 50 75 100

Question: If you could mate with a member of the opposite sex who was no more or less attractive than your permanent mate and there was no risk of disease, discovery or forming a permanent liaison, would you do it?

100

80

60

40

20

0Certainly

wouldProbably

wouldProbably not Certainly not

Probably/certainly not - Females - 91%

- Males - 50%

- Males

- Females

Most primates

Males concentration on mating effort

Females concentration on parental effort

Dominance in a Social Group

Environmental constraints

Group structure

Male strategies Female strategies


Underlying principle:

Higher status males more copulations & more offspring


Kipsigis

Acres owned

#wives

Dominance in Social Group

12 - 14

15 - 16

17 - 19

Age at puberty

Bride price

52-61 62-71 72-81 82-91

Decade

Ecology of human mating systems

Protein deficiency

Starvation

Subsistence

Female contribution

Marriage system

Population density

Mobility

Group size

Pathogens

Rain predictibility

Rainfall extremes

Temperature extremes

Food storage/trade

Ecology of human mating systems

If there are no resources???

Wives

Children

Unokai Non-UnokaiAge

20-24 25-30 31-40 >40

Wives

More wives earlier in life

Unokai – Yanomami warriors (involved in a killing)

Human mating systems

Sperm competitionHow monogamous is monogamy?

Indigo bunting

Days before egglaying

12 0

Extra-pair

Within pair


Sperm competition

When does it occur?

1. Adolescent courtship

Triobrand Islands


Sperm competition

When does it occur?

2. Facultative polyandry

polygyny monogamy

polyandryPolyandry


Sperm competition

When does it occur?

2. Facultative polyandry

polygyny monogamy

polyandryPolyandry

Facultative Polyandry

universal moderate occasional uncommon


Sperm competition

Why should females be polyandrous?

1. Good genes

2. Genetic Diversity

3. Fertility Backup

- 25% of couples - sterility (35% -male)

4. Material Resources

-females mate extramaritally more often with men of higher socioeconomic status

-females mate extramaritally more often with men older than their primary mate


Sperm competition

What attributes of humans may have evolved in context of sperm competition?

Males

1. Mating patterns

- most common -monogamy (with extramarital mating?)

-only if cost of any extramarital tactic is free or < cost of supporting second mate


Sperm competition


Males

2. Sexual Jealousy and Paternity Assurance

Spousal homocide related to sexual jealousy

USA - 33%Africa (several studies) - 45%


Sperm competition


Females

1. Cryptic ovulation and continuous sexual receptivity

Most primates Humans


Sperm competition


Females

2. Perennially obvious breasts

Human Mating Strategies. Some relevant facts: 1. Female investment in offspring – very high Male...

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