If a population of birds has individuals that are either small with short beaks or large with long beaks due to different feeding niches, what type of selection might this be, and what could be a long-term evolutionary outcome?

• A. Disruptive selection; it could lead to speciation as distinct feeding adaptations evolve.
• B. Directional selection; it shifts the population towards longer beaks.
• C. Stabilizing selection; it maintains an average beak size.
• D. Balancing selection; it prevents any beak size from becoming predominant.

Answer: (A)