Sex & Evolution Final Exam Study Guide
1. Sexual Jealousy
a) What do men & women stand to lose if their mates pursue extrapair copulations?
Men lose maternal/physical investment in their offspring & a sexual
partner as well, which could decrease their chances of reproducing
Women lose the financial investment of their husband as well as
b) Buss’s Study Page 199
Women are more emotionally jealous; don’t want their men to invest
feelings into another women or her children; don’t want to lose
Men are more sexually jealous; they like to be in charge and don’t
want anyone else to satisfy their woman; don’t want cuckoldry
2) Women’s Mating Strategies & Sexual Selection in Women
a) Competition is the activity of competing, in this case for the ideal male.
Women compete for men with:
* good status: wealthy, financial success, respected, these men
can pass on genes to male children that will increase their
chances of reaching a high status and attracting women like
their father’s, high status men also are more likely to
protect their women from unwanted attention
* good resources: wealth, prosperity, maturity, ambition,
financial success, land (in the cases of many tribal cultures)
*good genes/condition: symmetry, low FA, healthy, parasite
resistance these qualities are the basis of good
condition, which may be heritable and of genetic benefit
* a willingness to help them
Women compete for these men because men with these attributes
generally are better providers and are more capable of producing
offspring with these same characteristics. Women also compete over
men that they believe will provide the most financial and overall
paternal investment. Evolutionarily, the ideal man is worth competing for.
b) Forms of femalefemale competition
Direct: physically hitting their opponent, spreading rumors, threats,
attack and defense of reputation, etc.
Indirect: enticing men with the promise of fidelity, attractiveness &
youth, and sometimes dowries.
For direct competition, accusations of promiscuity or infidelity are a
frequent environmental cause of femalefemale aggression.
For indirect competition, literature that paints a picture of what a
man wants in a woman is a usual environmental factor.
fiercest competition occurs in highly stratified, strictly monogamous
3) Men’s Mating Strategies & Sexual Selection in Men
a) The 4 main mechanisms of sexual selection include:
Contests Overriding mechanism/most utilized
phylogeny: women compete over men instead
clustering of males & females
dimensionality of the mating environment : 3D
environment (such as the air) makes it hard to mate
guard therefore contests generally aren’t
effective; 2D environments (such as land) make it easier to
mate guard and protect against cuckoldry therefore
contests are more effective
* good genes: symmetry, low FA, attractiveness, sometimes
* investment: financial for women & physiological for men
Sperm Competition: sire choice mechanism (determines whose
sperm fathers offspring)/ Female orgasm: increases chances of
Sexual Coercion: rape
b) Predictions about mechanisms of sexual selection in humans:
We can make these predictions based on certain evolutionary,
physical aspects found within the male species.
Evidence: * Low to moderate sperm competition: In humans, testicle size
is generally a uniform trait, unlike in the animal kingdom,
therefore sperm competition is a less likely used mechanism in
* Moderate to high contests: Evidence has shown that men are
biologically built for competition. They have a high muscle
mass, a high fatfree mass, and an increased hand strength,
which are all signs that point to men being built for
competition. Men are also more likely to result
to physical violence and studies have shown that they
commit nearly all samesex homicides.
c) Contest competition doesn’t work as well for females because multifemale groups
makes contests less effective. Women also can’t constrain the choices of larger, more
aggressive males. Because of this, the primary mechanism of sexual selection in women is
mate attraction, which is dependent on mating context & menstrual phase.
4. Sexual Conflict & Rape
a) How do women’s and men’s reproductive strategies conflict?
Two reproductive strategies that women exhibit that may conflict
with men’s include their choice to either 1) secure or tiedown an
investing mate or 2) continue to flaunt their sexuality, which will
attract a cad, and put off a dad, who prefers evidence of fidelity.
i.e., threats to a man’s sexual access to females & threats to paternity
b) Social Science Explanation for Rape:
Men’s capacity to rape is the result of socialization – men learn to
Rape is not fundamentally a sexual act involving violence – it is a
violent act involving sex. Rape is a sexual manifestation of a male
desire to dominate a woman.
* Crosscultural studies & the presence of rape in many species
with no socialization at all challenges the belief that men
commit rape because they are exposed to patterns that
encourage it. * In most social scenes, social prescriptions are intended to
suppress rape, not encourage it.
* Studies indicate that rape occurs not so much because it is
encouraged, but because it is not appropriately penalized
* If rape WERE motivated primarily by a need for control, one
might expect those easiest to dominate (elderly women &
children) to be victimized the most the most victimized are
women in their twenties, the age group most willing and able
* It appears that the cause of rape is generally not the desire
for power, but the desire for sex and aggression and hostility
appear to be the tactics applied to achieve this
* The fact that sec acts are forced more often on sexually
attractive women suggests that the motives are sexual whether
or not the perps are conscious of these underlying motives
* Unanswered questions: why does rape occur in all societies?
Why are the men always rapists? Why are rape victims mainly
c) Rape: byproduct or adaptation?
Adaptation: Rape may be an adaptation that was favored by sexual
selection because it increased male reproductive success since it
increased the number of mates. There may be psychological
mechanisms designed specifically to influence males to rape in
ways that would have p