Cycle 10 Flashcards
Fitness benefit to recipient + Fitness benefit to actor (_______)
Cooperation
Fitness cost to recipient + Fitness benefit to actor (_______)
Selfishness
Fitness benefit to recipient + Fitness cost to actor (_____)
Spite
Individuals often appear to sacrifice their _____ for the good of others
fitness
Fitness cost to the recipient + Fitness cost to actor (______)
Altruism
Which type is most common and hard to reconcile with NS?
Altruism
Passing up opportunities to reproduce
Birds that help parents take care of children
Bees: whole groups of individuals that shut down ovaries and help the queen produce more sisters
EXAMPLE OF:
Ex: Reproductive altruism
One way individuals sacrifice their fitness:
Ex: Risking your own life for others
Is it “altruistic” to provide costly care to your descendants
NO: Parental care is not a problem for traditional NS theory
Providing care to your direct descents can be reconciled with how we think selection works
It isn’t exactly altruistic in the sense that you’re reducing your fitness because you sacrifice yourself so your offspring can survive (they are carrying your alleles, and your genes can survive/be passed onto the next generation)
____ selection: individuals act selflessly “for the good of the group”
Group
What is group selection and why is it not enough evidence?
Claimed that groups that are made up of good citizens will do better than groups composed of selfish individuals
We know now group selection is probably NOT a strong enough force to explain altruistic behaviors because even though yes, groups that are composed of mostly helpful individuals do better, it only takes one bad person to sneak in and be successful by others but not help
Free-rider problem
_______ theory:
Expands our view of fitness
Kin selection
_____ fitness
One way of getting your alleles into the next generation is by producing multiple offspring
Direct
_____ fitness
Also getting alleles by helping non-descent relatives survive and reproduce
Your relatives also have a lot of the same alleles that you do
indirect
If benefit to the actor’s indirect fitness outweighs the cost of the actor’s direct fitness, helping is favored by ______
kin selection
______ Rule: helpful behaviors favored if rb>c
Hamilton’s
_____ fitness
Direct fitness + indirect fitness
Inclusive
_____ (b) to actors relatives
Benefit
…does this outweigh the ___ (c) to actors’ direct fitness?
cost
Weighed by the degree of ______, r
relatedness
Five of your first cousins (r=0.125) and two of your half-siblings (r=0.25) are about to die. You have the opportunity to save them all, at the cost of your own life. According to kin selection, should you sacrifice yourself?
YES
(5x0.125) + (2x0.25) = 1.125 lives
1.125>1
A bird has the opportunity to help its parents raise four additional full siblings that would not have survived without its help OR to find a mate of its own and produce three offspring. What should the bird do?
(4x0.5) = 2
OR (3x0.5) = 1.5
Help raise siblings
Another bird, different options: Bird can help its mother and stepfather raise four additional half siblings that would not have survived without its help, OR to find a mate of its own and produce three offspring. What should the bird do?
(4x0.25) = 1
(3x0.5) = 1.5
Find a mate and produce its own offspring