lecture 15 - kinship Flashcards
why do female belding’s ground squirrels emit more alarm calls than males
females most often emit alarm calls because females stay in their natal area while men often emigrate from other places to find mates. This means that females find themselves around genetic kin and they want to warn them
what does kinship promote and deter
promote: prosocial behavior
deter: antisocial behavior
what is inclusive fitness
measure of individual total fitness based on number of offspring and contribution to reproductive success of genetic relatives
what is genetic relatedness equal to
probability that 2 individuals share alleles that are identical by descent (hamilton’s rule)
what is the relatedness of siblings? cousins? grandparent and grandchild? aunts/uncles and nieces/nephews?
Sibling → 0.5,
cousin → 0.25,
grandparent/grandchild → 0.25,
aunt/uncles & niece/nephew → 0.25
how does hamtilton’s rule help in making the decision to aid family members
decision based on how related the individuals are and the costs/benefits with the trait
when does natural selection favor kins helping another
when high relatedness
what were emlen’s predictions
1) Family groupings will be unstable, disintegrating when acceptable reproductive opportunities materialize elsewhere (if have higher inclusive fitness with group then stay but if can increase elsewhere then leave)
2) Families that control high-quality resources will be more stable than those with lower-quality resources
3) Assistance in rearing offspring (cooperative breeding) will be expressed to greatest extent between those family members that are closest genetic relatives
what is an example of emlen’s second prediction
in cooperatively breeding acorn woodpeckers, young birds survive better on territories with more storage holes and are more likely to remain on natal territory to create a “family dynasty”
what is an example of emlen’s third prediction
eusocial insects have colonies where only some individuals can reproduce and here sisters are super-relatives (since males are haploid and females are diploid) meaning that they have r=.75. genetic relatnedness is highest in social insect groups when queens are monandrous (single mate) and this is associated with eusociality
what is parent offspring conflict
at some stage, parents may decide to stop feeding offspring bc why die feeding offspring when you can have multiple reproductive seasons (favoring self which has r = 1)
what is sibling rivalry
kin selection theory predicts that indivi=uals should not be aggressive toward kin (like siblings) but if there are limited resources, conflict will increase because each individual is more related to itself (r=1) than to sib (r=0.5)
give example of sibling rivalry in egrets
in egrets, parents are unable to provide enough food to everyone at a point. egrets don’t all hatch at the same time and those that hatch earlier are able to get more of the food from parent because they have higher vertical positioning in the nest. so there is age-related dominance hierarchy
how to king and emperor penguins recognize kin
complex vocal cues that allow for kin recognition through ‘vocal signatures’
