When environmental conditions are stable we expect
A) an increase in the variation of the trait, i.e., the normal distribution to become wider.
B) individuals at the extreme ends of the normal distribution to do best.
C) the average phenotype to shift markedly.
D) the optimal phenotype to be near the population's average.

Question

Quizplus · Accepted Answer

In stable environmental conditions, natural selection tends to favor the individuals with traits that are close to the population average, leading to the optimal phenotype being near this average. This is because extreme traits are less likely to be advantageous when conditions are stable and not changing, making the average phenotype the most adapted to the current conditions.

When Environmental Conditions Are Stable We Expect