Which of the following statements about wolves in Yellowstone National Park is true?
A) They are the only predators of moose and elk.
B) Their disappearance led directly to the severe reduction of young aspen trees.
C) Their disappearance led indirectly to the severe reduction of young aspen trees.
D) Both a and b
E) Both a and c

Question

Quizplus · Accepted Answer

The disappearance of wolves in Yellowstone led to an increase in elk populations, which over-browsed young aspen trees, causing their reduction. This is an indirect effect, as wolves are not the only predators of moose and elk.

Which of the Following Statements About Wolves in Yellowstone National