Question

question 7 of 25
most of the mice in a population living in a forest clearing eat grass seed. however, a few mice climb the aquatic plants growing along a nearby creek and eat aquatic plant seeds, and a few larger mice forage for larger tree seeds in the forest.
a beaver dams the creek, which causes the forest clearing to flood. over time, the proportions of mice that eat aquatic plant seeds and larger mice that eat forest tree seeds increase in the population. conversely, the proportion of mice that only eat grass seed decreases in the population.

what form of selection has taken place in this population?
○ frequency - dependent selection
○ stabilizing selection
○ directional selection
○ disruptive (diversifying) selection

Explanation:

Disruptive selection favors extreme phenotypes over intermediate ones. Here, the flooding made grass seeds (intermediate food source) less available, increasing the proportion of mice eating aquatic seeds (one extreme) and tree seeds (another extreme), while decreasing the proportion of mice only eating grass seeds (intermediate). This matches the definition of disruptive selection.

Answer:

disruptive (diversifying) selection