Lecture 3- Sexual Selection Flashcards
What is monogamy?
Long standing pair bonds.
What is polyandry?
When females have multiple partners.
What is polygyny?
When males have multiple partners.
What is polygamy?
Everyone has multiple partners.
What is sexual dimorphism?
The differences in appearance between males and females such as colour that are caused by the inheritance of one sexual pattern- differences other than genitals.
What is intrasexual competition?
Within sex competitions- men compete for women.
What is intersexual competition?
One tries to attract the other with ornaments and displays.
What is the use of an ornament?
Ornaments are varied complex and costly to survival- they are used to draw in the opposite sex such as bright feathers.
Why do females do the choosing?
Trivers (1972) argues parental investment theory.
- females choose because costly investment, limited supply of eggs, 9mths gestation, dangerous birth.
- males contribute one orgasm.
What does choosiness depend on? (5)
Depends on mating system.
Females pay a high price for mistakes.
Males choosiness increases with investment.
Makes choosing if they rear.
Monogamous species have similar choosiness between the sexes.
Can ornamentation influence mate choice ?
Anderson (1982)
- found that artificially enhanced tails led to greater mating success.
- Females preferred to mate with males with longer tails.
Edme et al (2017)
- found that there are different benefits of male ornaments and female mate choice between population and species.
What is a fisherman mode of sexual selection?
Fisher- fisherman runway.
Positive feedback between heritable ornaments and preferences.
Due to females preferences birds may inherit the preference for brightness as well as benign bright themselves.
What researcher studied runaway in humans?
Stulp (2015)
Height has increased globally as diet and nutrition increased.
8 inches over 150 years.
Taller men have 11% more children.
