Exam 23: Ecological Communities

Follicle mites live in the hair follicles of human skin.They feed on single cells but do little if any harm to the human; the mite has a stable place to live and reproduce.This is an example of ________.

Pollinators ingest seeds at the flowers they visit,carry those seeds in their digestive tracts,and later deposit them far from the plant that they fed on.

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

Human-caused changes in ecological communities can be considered unique because

The consumer in a predator-prey interaction can be a selective force in the evolution of the prey species.

These shorebirds illustrate niche partitioning; each species has a specialized bill that permits it to feed in ways that reduce competition with other shorebirds living in the community.How might a biologist explain niche partitioning?

As the following figure illustrates,the distribution of numerous intertidal organisms is restricted to bands or zones.The upper limit to the zone is determined by tolerance to physical factors such as desiccation,whereas the lower boundary is determined by a biological interaction such as competition. What could account for the lower limit for Semibalanus?

An animal eats fruit from a plant and later deposits seed in its feces far from the plant.This is an example of a

Black oak trees are one of the earliest colonists after bare sand dunes are created.

Secondary succession is more likely to follow a disturbance to a mature community than primary succession because ________ typically remain intact.

In the centers of their ranges,two species of hummingbirds have very similar tongue lengths,but where the ranges overlap,one species has a shorter tongue and the other a longer tongue.This would most likely be an example of

If researchers were to document that the diversity of anemones lacking resident clownfish was approximately equal to those with clownfish,it would suggest that the interaction between these two species was

The living corals in tropical reefs have a profound affect on the hundreds of species that live in association with the reef and one another,yet corals are not considered keystone species because

The inhabitants of an aquarium,despite its small size,could be considered a community.

When different species of birds compete to use an abandoned woodpecker cavity,the successful competitor directly prevents the use of that resource by all others.This is an example of ________ competition.

Cattle grazing has a surprisingly harmful affect on dry grassland of the southwestern United States.What aspect of grazing is most likely responsible?

Mistletoe participates in forest communities in many beneficial roles; its berries and leaves are food for herbivorous birds and insects,but to the trees that host it,mistletoe is strictly an undesirable ________.

Communities change with respect to several timescales; an example of long-term change would be the

Which of the following best illustrates behavioral mutualism?

The association of populations of different species that live in the same area is a(n)________ .