life history Flashcards
define life history
pattern of investment an organism makes in growth and reproduction
operational sex ratio
Operational sex ratio refers to the ratio of sexually active males to sexually receptive females in a population at any given time.
sex ratio distortion
organisms may regulate offspring number to maximize fitness (sex ratio distortion)
- miscarriage
- cannibalism
organisms may regulate offspring sex ratio to maximize fitness
- more of one sex then the other
sex ratio adjustment - trivers willard hypothesis
natural selection can drive
mothers alter sex ratio depending on their condition (producing females when poor, producing males when good)
parent offspring conflict
what is most beneficial to mom is not often same as what it is for kid
parents and offspring disagree wrt investment
optimal allocation of parental investment depending differs on perspective
post posing senescence (aging)
senescence - deterioration with age
- caloric restriction
- age more slowly = have lower fitness
the longer u give birth, the longer u live = non human primates
mother hypothesis
reproduction late in life is risky (invest in current offspring)
grandmother hypothesis
loss of fertility shifts investment onto grandchildren (maintain strength)
