Birds with average-size wings survived a severe storm more successfully than other birds in the same population with longer or shorter wings. If severe storms occur regularly, then over time, one should expect these storms to bring about __________.

• A. the bottleneck effect
• B. directional selection
• C. gene flow
• D. disruptive selection
• E. stabilizing selection

Answer: (E)

Verified step by step guidance

1. Understand the concept of stabilizing selection: It is a type of natural selection that favors the average individuals in a population. This means that individuals with extreme traits are less likely to survive and reproduce.
2. Identify the scenario: Birds with average-size wings survived a severe storm more successfully than those with longer or shorter wings. This indicates that the average trait (wing size) is being favored.
3. Relate the scenario to stabilizing selection: Since the average wing size is favored and extremes are selected against, this is a classic example of stabilizing selection.
4. Consider the long-term effects: If severe storms occur regularly, birds with average-size wings will continue to have a survival advantage, leading to a population where most individuals have average-size wings.
5. Conclude that the correct answer is stabilizing selection, as it describes the process where intermediate traits are favored over extreme ones in a stable environment.