Question

Martinsen et al. (1998) determined that a beetle (C. confluens) preferred to eat leaves on cottonwood sprouts growing from the stumps of trees that beavers had cut down. They concluded that this interaction was an example of

Select one:

a. apparent competition

b. a keystone species effect

c. an indirect commensalism

d. an indirect mutualism

Answer 1

The correct option is C - an indirect commensalism

In commensalism, one species is benefited and another species is neither benefited nor harmed. In indirect commensalism, the act of one species indirectly benefits another species and the former is neither harmed nor benefited. In indirect commensalism, one species indirectly benefits another species through an intermediate species. Beaver cut down cottonwood trees and sprouts grown from the stumps of trees. And beetles eat sprout leaves that provide better nutrition and also uses the chemicals in the sprout leaves as a defense against predators. Here the beaver herbivory indirectly benefits beetles. Beavers benefit beetles through cottonwood. Beavers are neither benefited nor harmed. This interaction between beavers and beetles is an example of an indirect commensalism

Hence, the correct option is C