A Virgin Pine Forest Covers a Valley,and One of the Inhabitants

Multiple Choice

A virgin pine forest covers a valley,and one of the inhabitants is a red squirrel species.A large volcanic eruption occurs and separates the valley with a huge lava flow,thus producing two populations of squirrels.What must occur for the two populations of squirrels to be considered separate species?

A) The two squirrel populations must feed on different species of plants.
B) The environment must change so that the populations exist in distinct habitats.
C) The fur color or other morphological characteristic of the two squirrel populations must become distinct.
D) The two squirrel populations must select mates using different behaviors.
E) The two squirrel populations must be reproductively isolated.