Sexual Selection Theory

Evolutionary Explanations of Relationships Understand concept of Sexual Selection

Reminder

What are the 6 stages of Rollie and Ducks model of Relationship Dissolution? BIPDSGDR

Name one study in support of Duck

How did Akert et al criticise this model?

Economic vs. evolutionary3

Evolutionary PsychologyAll behaviour is rooted in:1. Survival2. Ensuring reproductive success

Phobias, anorexia, gym, make up, dancing 4

Sexual SelectionNatural Selection the most basic process of evolution

Those who are best adapted to their environment will survive.Survival of the fittest

Surviving is futile if you dont pass on your genes and create a genetic lineage

Sexual SelectionThe probability of passing on our genes depends on survival but also our ability to attract a mate

Sexual Selection

Sexual Selection is the process by which a species changes over time as a result of passing on genes that make one individual more attractive to the opposite sex.

More attractive than others7

Sexual Selection

Adaptations occur as a result of competition

Sexual Selection occurs as a result of competition for mates

Natural Selection vs Sexual SelectionSurvival of the fittest vs. Survival of the sexiest!

Sexual Selection

Sexual selection is driven from Mate Preference

Female Pehen wants the most colourful maleMale Peacock wants the healthiest female

Sexual selection is driven from Mate Preference

Female Pehen wants the most colourful maleMale Peacock wants the healthiest female

10

Mate Preference in Humans

Singh (1993)

Across cultures, there is a male preference for low waist-ratios (0.7) in women

This produces a typical hour-glass shape

Preference exists despite differences in weight preferences across cultures

Formation of Relationships11

Singh et al (1993)

Preferences for shape A was found cross-culturally

Hour Glass figures demonstrate fertility.

This is an appealing characteristic for a reproductive male

David Buss (1989)

Cross-cultural study

Questionnaire given to men and women asking about mate-preferences

Your task get a minimum of 1 male and 1 female to fill out this questionnaire Bring your results to Mondays lesson

Sexual Selection

Physical Characteristics may have evolved in order to attract a mate rather than survive

Sexual Selection can also influence our behaviour

14

Reproductive Behaviour

Behaviour patterns associated with courtship, copulation and post-copulatory behaviour

15

Reproductive Behaviour in humans

Differences in Quantity of mates

Differences in Longevity of mates

Differences in Sexual Jealousy

Differences in Sexual Fantasies