31. Population ecologists follow the fate of same-age cohorts in order to
(A) determine the factors that regulate the size of a population.
(B) determine a population's carrying capacity.
(C) determine if a population is regulated by density-dependent processes.
(D) determine the birth rate and death rate of each age group in a population.
(E) determine if a population's growth is cyclical.

27. Coral reefs can be found on the southern east coast of the United States but not at similar latitudes on the southern west coast. Differences in which of the following most likely account for this? (A) ocean currents (B) precipitation (C) sunlight (D) day length (E) salinity

28. Polar regions are cooler than the equator because (A) the poles are permanently tilted away from the sun. (B) there is more ice at the poles. (C) the poles have a thicker atmosphere. (D) sunlight strikes the poles at an oblique angle. (E) the poles are farther from the sun.

29. Reconciliation behavior is likely to follow (A) imprinting by young animals on a member of the wrong species. (B) conflict behavior between members of a permanent social group. (C) mating behavior between a male and a female. (D) agonistic behavior between territorial males. (E) ritualized behavior.

30. In the 14th century, _____ was responsible for the death of more than one-third of the entire European population of humans. (A) pneumonia (B) bubonic plague (C) AIDS (D) influenza (E) tuberculosis

32. The growing season would generally be shortest in which of the following biomes? (A) taiga (B) temperate broadleaf forest (C) savanna (D) tropical rain forest (E) temperate grassland

33. Which marine zone would have the lowest rates of primary productivity (photosynthesis)? (A) abyssal (B) intertidal (C) neritic (D) continental shelf (E) pelagic

34. In the territorial behavior of the stickleback fish, the red belly of one male elicits attack from another male by functioning as (A) a pheromone. (B) a sign stimulus. (C) an imprint stimulus. (D) a fixed action pattern. (E) a search image.

35. Life history strategies usually result from (A) environmental pressures. (B) natural selection. (C) conscious choice. (D) A and B only (E) A, B, and C

36. A recent study of ecological footprints (described in the text) concluded that (A) it is not possible for technological improvements to increase Earth's carrying capacity for humans. (B) current demand by industrialized countries is much smaller than the ecological footprint of those countries. (C) the ecological footprint of the United States is larger than the ecological capacity of its land. (D) Earth's carrying capacity would increase if per capita meat consumption increased. (E) Earth's carrying capacity for humans is about 10 billion.

37. Which of the following members of a marine food chain is most analogous to a grasshopper in a terrestrial food chain? (A) shark (B) zooplankton (C) phytoplankton (D) detritivore (E) fish