Question

The concept of stabilizing selection is described by

• A. Graph I only
• B. Graph II only
• C. Both Graph I and Graph II
• D. Graph III only
• E. Both Graph II and Graph III

Answer 1

Answer: (A)

Graph I only

When natural selection tends to decrease genetic diversity and the mean value of population stabilizes over a particular trait, it is referred to as stabilizing selection (graph I). Directional selection favors one of the extreme traits and shifts the graph over that trait (graph II) while disruptive selection favors both extreme traits (graph III). Thus, the correct answer is option A.