Lecture 4

Question 1

What are the main two types of questions when talking about mechanisms and causes

Answer 1

Proximate mechanisms (cognition's, emotions, behaviours and hormones).
Ultimate causes (how fitness enhanced?)

Question 2

What is the origin of sex and explain it?

Answer 2

Endosymbiosis; Start with two independent bacteria, one engulfs the other and now one lives inside the other. Both bacteria benefit from the arrangement and the internal bacteria are passed on from generation to generation

Question 3

Is the sexual dimorphism in humans?

Answer 3

Mild-moderate sexual dimporhism! Males are usually larger than females etc.

Question 4

Discuss the relationship between body and testicle size

Answer 4

Increasing testicle size = decrease in sexual dimorphism. Small testicles = large physical dimorphism, low sperm count and monandrous. Medium testicles = moderate dimorphism, some sperm competition and mixed mating strategies. Large testicles = small physical dimorphism, high sperm competition and promiscuous

Question 5

Discuss infidelity in humans

Answer 5

Many human societies are monogamous or polygamous. Extra-pair copulation’s are common in both sexes. Official marriage system is NOT unofficial mating system. Prevalence of sexual infidelity difficult to measure; 20-25% US marriages, 65-75% have experienced extradyadic involvement whilst in a serious relationship.

Question 6

Discuss briefly infidelity in animals

Answer 6

It is seen in apparently monogamous animal species; both males and females. Some bird species have 10-40% chicks fathered by a male other than the pair bonded mate

Question 7

Discuss male infidelity

Answer 7

More partners = more offspring. Men are more likely to report having affairs that were just sex. Not necessarily linked to dissatisfaction with current relationship.

Question 8

Discuss female infidelity

Answer 8

Quality based strategy for optimising offspring survival. Best physical specimens may not be the best resource providers. Infidelity more strongly linked to dissatisfaction with current relationship. Female affairs may be practising “facultative polyandry”; seemingly monogamous but selecting sperm from particular males

Question 9

Discuss the effects of women at peak estrus

Answer 9

Flirt more, show more skin, wear more jewellery, have affairs, prefer more testosteronised males, earn more tips as erotic dancers

Question 10

Does infidelity serve different purposes in males and females?

Answer 10

Males are less likely to forgive and more likely to break up with sexually unfaithful partner. Females seem more sensitive than males to emotional infidelity

Question 11

What predicts deep orgasms

Answer 11

Vigour; Smell; Dominance; Considerateness

Question 12

What did Atkipis and Bryant (2014) find

Answer 12

Compared real and fake laughs, found laughter is an honest signal of co-operative intent.

Question 13

What is one theory of female orgasm?

Answer 13

To retain sperm