MC. An island in the Galapagos has a resident population of marine iguanas. Their only historical predator is a hawk which is able to catch small and large individuals with equal ease. If rats were introduced to the island, and preferentially attacked smaller iguanas, you might expect to see iguana body size to __________ and the population to be under __________ selection.

a. increase; directional

b. increase; disruptive

c. decrease; directional

d. decrease; stabilizing

e. stay the same; stabilizing

MC. Suppose 36% of a remote mountain village can taste phenylthiocarbamide (PTC) and must therefore have at least one copy of the dominant PTC taster allele. If we assume this population is approximately consistent with Hardy-Weinberg assumptions for this gene, approximately what percentage of the population should be heterozygous for this trait?

a. 16%

b. 32%

c. 40%

d. 48%

e. 60%

MC. When Darwin studied the finch population of the Galápagos Islands, he observed a variation of beak sizes related to the size of seeds available on their respective islands. Larger beaks were better adapted for larger seeds, and smaller beaks were better adapted for smaller seeds, making medium sized beaks maladaptive. This is an example of

a. Directional selection

b. Mutational Drift

c. Disruptive selection

d. Genetic Flow

MC. Two frog populations of the same species live at different lakes. They have developed slight differences in appearance, but these differences seem to make no difference to their survival or reproduction. The differences seem to be heritable, and hybrid offspring have intermediate appearance, and seem to have the same fitness as the parent populations. A change in climate makes the area wetter, and increases the amount of interaction and inter-breeding between the two populations. What result would you expect?

A. Lower average fitness in both populations

B. Higher average fitness in both populations

C. Increased genetic difference between the two populations

D. Decreased genetic difference between the two populations

E. Increased genetic drift

MC. If piperfish males invest more energy in raising offspring than females, and females are larger and showier than the males, which of the following would you expect to be true?

A. Males are more choosy about mates, and have larger variation in reproductive success.

B. Females are more choosy about mates, and have larger variation in reproductive success.

C. Males are more choosy about mates, and females have larger variation in reproductive success.

D. Females are more choosy about mates, and males have larger variation in reproductive success.

E. Both sexes are equally choosy about mates, but females have larger variation in reproductive success.