Natural Selection (3) Flashcards
Male Strategies - Optimal Reproductive Strategy
Exclusive access to fertile females
High fitness means
more babies
A reminder what is the limiting factor to females and why is it limiting to females? (2)
1) Acquisition of rich dense food
2) Due to energy expedition of reproductive functions - lactation, gestation, lactational amenorhhea
A reminder what is the limiting factor to males and why is it limiting to males?
1) Access to females in Estrus & because competition / SS
What is Estrus
The period around ovulation where females can conceive
The male’s optimum strategy creates 2 conflicts: Go fo as many Fertilizations as possible - 2 Conflicts
1) Other males - intracompetition
2) Females selective nature ( they want best genes for survival )
What can males do to access to reproductive opportunities? (3)
1) Try to influence female choice
2) Compete with other males
3) Sexual Coercion
What can males do to access to reproductive opportunities? Try to influence female choice - Inter Sexual selection
Convincing females to mate with them by advertising their good genes (fitness/resource holding potential)
What can males do to access to reproductive opportunities? Try to influence female choice - Inter Sexual selection - Example
Bigger bodies female find this attractive
What can males do to access to reproductive opportunities? Try to influence female choice - Inter Sexual selection - Example - Bigger bodies who shows this?
Gorillas & Orangutans
What can males do to access to reproductive opportunities? Try to influence female choice - Inter Sexual selection - Example - larger voices example
Male orangutans (throat sacs) & females dig this they appear bigger
What can males do to access to reproductive opportunities? Try to influence female choice - Inter Sexual selection - Example - Colouration
Attracts females because bright colours means your healthy
What can males do to access to reproductive opportunities? Try to influence female choice - Inter Sexual selection - Example - Colouration
Madrill
What can males do to access to reproductive opportunities? Try to influence female choice -Friendships: Matting Effort Hypothesis
You’re nice to non-fertile women to show your willingness to invest in an infant, male friends increase their chances of fitness when female become Estrus
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization
Males monopolize by force females that are estrus
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - Who does this
Gorillas
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - Group Types (2)
1) uni male groups
2) Multi male groups
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - Group Types - Uni male groups what is it ?
males form uni male groups by evicting natal males and preventing dispersing males from joining them
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - Group Types - Uni male - consequences of competition
- Low within-group competition over females
2. high competition between groups
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - Group Types - Males that live in multi-male environment (2)
High within-group competition over access to females
lower between-group competition
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - What does it depend on for females to be monopolized (2)
1) The number of females within a group - the more the harder
2) The distribution of Estrus females
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - What does it depend on for females to be monopolized - The distribution of Estrus females (2)
1) Asynchronous
2) Synchronous
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - What does it depend on for females to be monopolized - The distribution of Estrus females - Asynchronous ?
A single man has a HIGHER chance of monopolizing access to females
periods not synchronized such as synchronous processs
What can males do to access to reproductive opportunities? Males will compete with each other: Strategy: Male Monopolization - What does it depend on for females to be monopolized - The distribution of Estrus females - Synchronous?
A single man has a LOWER chance of monopolizing access to females due the fact that the female population have synchronized their estrus cycles
- period matching