ANTH 216 ANTH216 Problem Set 3 Answers (Penn State) – Online Homework Help
ANTH 216 Problem Set 3 Solution (Penn State University)
1. In “harem” species, breeding groups consist of a breeding male and several adult females. There is a lot of competition to be a harem-holding male; many males don’t have harems and attack harem-holding males in efforts to take over. In several mammal species, a successful invader kills the dependent young. This causes nursing females to stop lactating and return to a state where they can conceive new offspring. Some biologists have argued that such infanticide serves the function of population regulation, keeping the number of individuals down, so they will not exhaust their food supply.
a. In the population- regulation explanation, at what level is selection supposedly acting?
b. If the population- regulation explanation is correct, when would you expect this behavior to occur? In other words, on what should it be facultatively dependent?
c. On what does it seem to be facultatively dependent?
d. How do these facts affect your confidence in the population- regulation explanation?
e. Can you offer any other ultimate explanations for this facultative infanticide? Hint: Who might benefit by it, and how might they benefit?
2. Just like infanticide, altruism is a bit of an evolutionary puzzle.
3. Hamilton’s theory about the “back door” is called “kin selection.” Explain the logic behind that term.
4. Hamilton’s rule for adaptive altruism is rb>c. Explain Hamilton’s rule.
5. How would you test Hamilton’s theory about the evolutionary causes of altruism? Hint: What does Hamilton’s rule predict?
Comments
Post a Comment