Exam 35: Interactions among Organisms

Certain species of squirrels and acorn woodpeckers both eat acorns. In forests without squirrels, the density of acorn woodpeckers averages 100 per square kilometer, whereas in forests with squirrels the density of acorn woodpeckers is roughly halved. This reduced density most probably results from

Due to competition, forms of competing species may evolve to become more different from each other over time. This change is known as character _______.

A _______ is an organism that transfers one plant's male reproductive cells to the female reproductive organs of another plant.

In the pollinator mutualism between the yucca plant and the yucca moth, the yucca plant is able to abort the seeds in any given flower if the moth lays too many eggs in that flower. What is the advantage the yucca plant gains by aborting these seeds?

Cowbirds lay their eggs in the nests of smaller birds. The fast-developing cowbird chicks hatch first, then push the other baby chicks out of the nest as they hatch. Which interaction best describes cowbird behavior?

The activity of predators has caused their prey to evolve a variety of protective characteristics. How were the prey able to acquire these new features?

Interactions among organisms are always mutually beneficial.

Pathogens are considered a special type of parasite because they

Which of the following could be an example of an induced response?

Mutualistic relationships can have an effect on the distribution and abundance of the species involved.

Which of the following combinations of symbols represents an interaction where one species benefits and the other is exploited?

In ____ competition, species compete indirectly for a shared resource, each reducing the amount available to the other competitor.

The geographic area over which a species is found is called its ____________.

Suppose that two species of hummingbirds have very similar tongue lengths in regions where only one of the two species occurs, but that one species has a shorter tongue and the other a longer tongue in regions where both species occur. This would most likely be an example of

Which of the following animals would be most likely to simultaneously participate in seed dispersal and a gut inhabitant mutualism?

Every healthy human digestive system is home to countless microorganisms. In a normal digestive system, what type of relationship would you say this is?

Explain the relationship between the prevalence of schistosomiasis and the use of molluscicide in tropical regions like Nigeria.

Which of the following best illustrates behavioral mutualism?

_______ competition occurs when one organism directly keeps another organism from using a resource; for example, two species of birds attempting to use an abandoned woodpecker cavity.

Without pollinator mutualism, agricultural productivity could fall significantly.