LSAT Prep 101 section 4

pTest 101 / Section 4 Directions Passage Only View Find Text. Type Here U AA I= | Section Time Remaining: 17:43 When the same habitat types (forests, oceans, grasslands, etc.) 17. As presented in the passage, the principles of the time theory in regions of different latitudes are compared, it becomes apparent most strongly support which one of the following predictions? that the overall number of species increases from pole to equator. This latitudinal gradient is probably even more pronounced than current records indicate, since researchers believe that most A In the absence of additional ice ages, the number of undiscovered species live in the tropics. species at high latitudes could eventually increase significantly. One hypothesis to explain this phenomenon, the "'time theory, holds that diverse species adapted to today's climatic conditions have had more time to emerge in the tropical regions, which, unlike B) No future ice ages are likely to change the climatic O the temperate and arctic zones, have been unaffected by a conditions that currently characterize temperate regions. succession of ice ages. However, ice ages have caused less disruption in some temperate regions than in others and have not If no further ice ages occur, climatic conditions at high O interrupted arctic conditions. latitudes might eventually resemble those at today's tropical latitudes Alternatively, the species-energy hypothesis proposes the following positive correlations: incoming energy from the Sun correlated with rates of growth and reproduction; rates of growth D) Researchers will continue to find many more new species O and reproduction with the amount of living matter (biomass) at a in the tropics than in the arctic and temperate zones. given moment; and the amount of biomass with number of species However, since organisms may die rapidly, high production rates can exist with low biomass. And high biomass can exist with few Future ice ages are likely to interrupt the climatic O species. Moreover, the mechanism proposed-greater energy conditions that now characterize high-latitude regions. influx leading to bigger populations, thereby lowering the probability of local extinction- remains untested. A third hypothesis centers on the tropics climatic stability, which provides a more reliable supply of resources. Species can thus 1 2 3 4 20 21 22 23 24 25 45