Exam 54: Biodiversity and Communities

Scientists interested in how populations interact within communities are attempting to determine the species diversity of an island under study. Which of the following data would be most helpful to the scientists in determining diversity?

Predators that are keystone species can maintain species diversity in a community if they ________.

Use the figure to answer the following question. Which of the following conclusions is best supported from the experimental evidence in the figure?

Using the symbols +, −, and 0 to indicate interspecific species interactions, where the first symbol refers to the first organism mentioned, what interactions exist between cellulose-digesting organisms in the gut of a termite and the termite?

Dwarf mistletoes are flowering plants that grow on certain forest trees. They obtain nutrients and water from the vascular tissues of the trees. The trees derive no known benefits from the dwarf mistletoes, yet they are sometimes negatively affected by this interaction. Which of the following best describes the interactions between dwarf mistletoes and trees?

Biological communities may show a highly predictable and interrelated structure, or alternatively, the individual species may appear to operate independently. If a researcher were to set up many identical sterilized ponds in the same area and allowed them to be colonized, which result would support the idea that species operate independently?

Some birds follow moving swarms of army ants in the tropics. As the ants march along the forest floor hunting insects and small vertebrates, birds follow behind and eat any insects or small vertebrates that had flown jumped away from the moving swarm. Which of the following species interactions does this example demonstrate between the birds and the ants?

Which of the following best explains why there are more species in tropical regions than in locations more distant from the equator?

Elephants are not the most abundant species in African grasslands, yet they influence community structure. The grasslands contain scattered woody plants, but these woody plants remain relatively uncommon because of the uprooting activities of the elephants. If elephants were removed, the grasslands eventually are converted to forests or to shrublands. These newly growing forests support fewer species than the previous, more biodiverse grasslands. Which of the following statements best supports the elephants' role as a keystone species in this scenario?

Approximately how many kilograms (kg) of carnivore (secondary consumer) biomass can be supported by an area of a field containing 1,000 kg of plant material (assuming 10% efficiency in energy transfer)?

Which of the following statements is consistent with the principle of competitive exclusion?