Campbell Biology

Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson

Chapter 51

Animal Behavior - all with Video Answers

Educators

Chapter Questions

Problem 1

Which of the following is true of innate behaviors?
a. Their expression is only weakly influenced by genes.
b. They occur with or without environmental stimuli.
c. They are expressed in most individuals in a population.
d. They occur in invertebrates and some vertebrates but not mammals.

Jennifer Smith

Jennifer Smith

Numerade Educator

Problem 2

According to Hamilton's rule,
a. natural selection does not favor altruistic behavior that causes the death of the altruist.
b. natural selection favors altruistic acts when the resulting benefit to the recipient, corrected for relatedness, exceeds the cost to the altruist.
c. natural selection is more likely to favor altruistic behavior that benefits an offspring than altruistic behavior that benefits a sibling.
d. the effects of kin selection are larger than the effects of direct natural selection on individuals.

Jennifer Smith

Numerade Educator

Problem 3

Female spotted sandpipers aggressively court males and, after mating, leave the clutch of young for the male to incubate. This sequence may be repeated several times with different males until no available males remain, forcing the female to incubate her last clutch. Which of the following terms best describes this behavior?
a. polygyny
b. polyandry
c. promiscuity
d. certainty of paternity

Jennifer Smith

Numerade Educator

Problem 4

A region of the canary forebrain shrinks during the nonbreeding season and enlarges when breeding season begins. This change is probably associated with the annual
a. addition of new syllables to a canary's song repertoire.
b. crystallization of subsong into adult songs.
c. sensitive period in which canary parents imprint on new offspring.
d. elimination of the memorized template for songs sung the previous year.

Jennifer Smith

Numerade Educator

Problem 5

Although many chimpanzees live in environments containing oil palm nuts, members of only a few populations use stones to crack open the nuts. The likely explanation is that
a. the behavioral difference is caused by genetic differences between populations.
b. members of different populations have different nutritional requirements.
c. the cultural tradition of using stones to crack nuts has arisen in only some populations.
d. members of different populations differ in learning ability.

Jennifer Smith

Numerade Educator

Problem 6

Which of the following is not required for a behavioral trait to evolve by natural selection?
a. In each individual, the form of the behavior is determined entirely by genes.
b. The behavior varies among individuals.
c. An individual's reproductive success depends in part on how the behavior is performed.
d. Some component of the behavior is genetically inherited.

Heather Thornton

Heather Thornton

Numerade Educator

Problem 7

You are considering two optimal foraging models for the behavior of a mussel-feeding shorebird, the oystercatcher. In model A, the energetic reward increases solely with mussel size. In model B, you take into consideration that larger mussels are more difficult to open. Draw a graph of reward (energy benefit on a scale of $0-10$ ) versus mussel length (scale of $0-70 \mathrm{mm}$ ) for each model. Assume that mussels under $10 \mathrm{mm}$ provide no benefit and are ignored by the birds. Also assume that mussels start becoming difficult to open when they reach $40 \mathrm{mm}$ in length and impossible to open when 70 mm long. Considering the graphs you have drawn, what observations and measurements would you make in this shorebird's habitat to help determine which model is more accurate?

Jennifer Smith

Numerade Educator

Problem 8

We often explain our behavior in terms of subjective feelings, motives, or reasons, but evolutionary explanations are based on reproductive fitness. What is the relationship between the two kinds of explanation? For instance, is a human explanation for behavior, such as "falling in love," incompatible with an evolutionary explanation?

Jennifer Smith

Numerade Educator

Problem 9

Scientists studying scrub jays found that "helpers" often assist mated pairs of birds in raising their young. The helpers lack territories and mates of their own. Instead, they help the territory owners gather food for their offspring. Propose a hypothesis to explain what advantage there might be for the helpers to engage in this behavior instead of seeking their own territories and mates. How would you test your hypothesis? If it is correct, what results would you expect your tests to yield?

Joanna Quigley

Numerade Educator

Problem 10

Researchers are very interested in studying identical twins separated at birth and raised apart. So far, the data reveal that such twins frequently have similar personalities, mannerisms, habits, and interests. What general question do you think researchers hope to answer by studying such twins? Why do identical twins make good subjects for this research? What are the potential pitfalls of this research? What abuses might occur if the studies are not evaluated critically?

Prashant Bana

Numerade Educator

Problem 11

Learning is defined as a change in behavior as a result of experience. In a short essay ( $100-150$ words), describe the role of heritable information in the acquisition of learning, using some examples from imprinting and associative learning.

Rikhil Makwana

Numerade Educator

Problem 12

Acorn woodpeckers (Melanerpes formicivorus) stash acorns in storage holes they drill in trees. When these woodpeckers breed, the offspring from previous years often help with parental duties. Activities of these nonbreeding helpers include incubating eggs and defending stashed acorns. What are some questions about the proximate and ultimate causation of these behaviors that a behavioral biologist might ask?

Prashant Bana

Numerade Educator