Exam 55: Species Interactions

Evidence suggests that some grasses benefit from being grazed.In an asymmetrical grazing interaction, which action of grazers would likely provide the most benefit to a grass species in this ecosystem?

Various types of aphids feed on the leaves of cottonwood trees.The larger aphids defend feeding sites on the most preferred leaves by kicking or shoving smaller aphids off the leaves.This is an example of

Which feature of a fruit would be least likely to attract or reward a frugivore?

The graph below shows cycles of predators (lynx) and prey (snowshoe hares) over nearly a century.During this time, people were trapping both lynx and hares, thus limiting their populations. If trapping of both species declined, what changes would be expected to occur in the hare and lynx populations?

A stressful environment, such as a desert, will likely have a high proportion of ecological interactions that are _______ (positive/negative/neutral).

Many stinging wasps that are not closely related have black-and-yellow striped abdomens and display similar behaviors.This example of Müllerian mimicry includes which type or types of prey defenses?

Which type of interaction best characterizes a disease-causing bacterium?

Which type of study would likely provide scientists with the best information on why lionfish are successfully invading the Western Atlantic and Caribbean?

An "honest" mimic that is genuinely unpalatable and mimics the coloration of another species that is also unpalatable is called a(n) _______ mimic.

Some types of pine trees are attacked and fed on by pine bark beetles.As the beetles feed, they girdle the trees, destroying the phloem layer and killing the trees.Pine bark beetles are also associated with the blue stain fungus, which grows in their frass (feces).As they attack the trees, the beetles also inject the fungus.The fungal hyphae grow into the tree and follow its xylem cells, blocking the flow of xylem and causing rapid tree death.This information suggests that the relationship between the pine bark beetle and fungus is _______, while the relationship between the beetle and the pine tree is _______.

Many scientists think the great number of parasite species on Earth can be explained by the specialization parasites have undergone and continue to undergo.Which factor is likely most responsible for the continued evolution of new forms of parasites?

In Robert Paine's study of sea star-mussel interactions in rocky shore communities of the Pacific Northwest, which species would be considered a keystone species and why?

Many species of parrotfishes inhabit coral reefs.These species have different feeding habits, swimming in and around the corals.Many large species, such as steephead parrotfish, feed by scraping algae from the substrate of the coral reef, exposing bare areas where new coral larvae can settle.Others, such as bumphead parrotfish, actually eat the coral, taking large bites from the coral skeleton and damaging its integrity, so it takes years to repair.How can these interactions best be characterized?

Why would it be particularly beneficial for sessile species, such as plants or corals, to develop positive interactions such as mutualisms or commensalisms?

Leaf cutter ants cannot survive without the fungus that they cultivate in their gardens, and the fungus in turn cannot survive without the ants.Which statement best describes this interaction?

Which interaction is not a trophic interaction?

A newly discovered frog species secretes toxic chemicals.Compared with closely related species without chemical defenses, members of this new frog species will most likely

The African savanna is flat and has few hiding places.In this environment, which characteristic is likely to be the greatest asset for a predator?

Anemonefishes can tolerate the stings of anemone tentacles, whereas most fish species cannot.An anemonefish lives among an anemone's tentacles, where the anemone protects it from its predators, butterfly fishes.This is an example of

Describe an experiment that would enable you to assess the degree of interspecific competition that exists between two rodent species living in the same habitat.How would you interpret the results?