In a population of birds, the average beak size is selected against and the large and small sized beaks are selected for. This is an example of
A) directional selection.
B) disruptive selection.
C) stabilizing selection.
D) natural selection.
E) balanced polymorphism.

Question

Quizplus · Accepted Answer

Disruptive selection occurs when extreme traits are favored over intermediate traits, leading to a bimodal distribution of traits. In this case, the extreme traits are large and small beak sizes, which are selected for, while the intermediate trait (average beak size) is selected against. This is different from directional selection where one extreme trait is favored over the other, and stabilizing selection where intermediate traits are favored over both extremes. Natural selection is the process by which certain traits become more or less common in a population based on their impact on survival and reproduction. Balanced polymorphism occurs when multiple alleles for a gene are maintained in a population at relatively stable frequencies.

In a Population of Birds, the Average Beak Size Is