lecture 8 - life histories

Question 1

what is senescence?

Answer 1

at around 80 years, multiple physiological processes deteriorate rapidly

Question 2

what is the extrinsic mortality risk?

Answer 2

the probability of an individual dying in a given time period through events in the environment e.g fluctuations in food supply, accidents, weather fluctuations etc

Question 3

who examined life expectancy and reproductive behaviour across 77 neighbourhoods in Chicago?

Answer 3

Wilson and Daly - they found life expectancies varied dramatically across neighbourhoods
- where life expectancies are low women have more babies and have them younger in life

Question 4

what is the Trivers-Willard hypothesis?

Answer 4

females will always be able to find mates, whereas males won’t

Question 5

Is there a Trivers-Willard effect in humans?

Answer 5

good maternal nutritional status produces larger offspring and has a more beneficial effect on male than female reproductive success

Question 6

what does the disposable soma theory show?

Answer 6

due to extrinsic mortality it can be adaptive not to perfectly repair the soma, but instead to divert the energy to reproduction - even though this eventually leads to senescence and death

Question 7

why do organisms trade off the qual of their offspring against the quan?

Answer 7

as it leads to the evolution of a clutch or litter size smaller than the largest they could produce

Question 8

what is more adaptive?
1- females in good condition to bear more sons
OR
2 - females in poor conditions to bear more daughters?

Answer 8

1

Question 9

what are parents and offspring in conflict over?

Answer 9

the amount of energy allocated to care

Question 10

why have females evolved menopause as an adaptive switch from reproductive effort?

Answer 10

increases their fitness via grandmothering later in life