2. (15 pts) As part of your critique of this study, you note that it uses
a correlational approach to explore the relationship between parasite load
and female mating preferences. Briefly outline an experimental approach
to this question that could be used to address this question. Why is your
experimental study a better test of the relationship between parasite load
and female choice than the original study described above?
3. (10 pts) In a study of crested auklets (shown below), a behavioral ecologist found positive correlations between the size of the crest on a male, the number of females mated with, and the number of chicks sired by a male. Based on these data, the researcher concluded that “the tuft of feathers on the male’s head is an adaptation that evolved to attract females.” Do you agree or disagree with this conclusion? Explain your answer.
4. (10 pts) In the lecture on game theory, you learned that constructing a payoff matrix is the critical step in developing any game theory model. What is a payoff matrix? What important information does a payoff matrix provide that helps us to understand why individuals exhibit particular behavioral responses during social interactions with conspecifics?
5. (10 pts) As part of a study of mate choice in guppies, you are interested
in documenting the number of female glide displays (indicative of sexual
receptivity) that are elicited by males with different amounts of orange
pigmentation. Assuming that this study takes place in the classic 3-compartment
aquarium set up that we discussed in class, which technique for collecting
observational data is most appropriate for examining the relationship between
male coloration and female display rate? Explain your answer.
6. (15 pts) As a professor of behavioral ecology, you are approached by a
student who is studying sexual selection in Harris sparrows. Specifically,
this student hypothesizes that dark coloration on the head and chest is
indicative of male quality, or “good genes.” This student has
successfully demonstrated that females prefer darker males, that darker
males survive longer, and that darker males sire more offspring. Based
on these data, the student would like to finish their thesis and publish
their study. You respond by telling the student that they aren’t
done yet – the student needs to conduct one more study that examines
the survival of chicks sired by dark versus light male sparrows. Why is
this last study necessary to test the good genes hypothesis? If dark color
in male Harris sparrows is an example of the good genes model of sexual
selection, what should the relationship between male darkness and chick
survival look like?
7. (10 pts) If the student finds that the relationship predicted above for male darkness and chick survival is correct, can this student definitively conclude that plumage coloration in male Harris sparrows is the result of a good genes model of sexual selection? Why or why not?
8. (10 pts) As you read the student’s thesis more closely, you notice
that the student measured male reproductive success by counting the number
of chicks that survived to fledging (independence from parents). Was this
the best measure of male fitness to use for this research problem? Why or
why not? If you answer yes, briefly explain why this is the best measure.
If you answer no, briefly indicate why this measure may be problematic.
9. (10 pts) The use of molecular genetic techniques to accurately determine the parentage and reproductive success is often said to have revolutionized the study of animal mating systems. List two discoveries about animal mating systems that have resulted from our ability to obtain accurate data on parentage and reproductive success. Briefly explain each discovery and how it has affected our understanding of patterns of reproductive competition in animals.
#1.
#2.