Question

1. in a population of seed - eating birds, the supply of medium - sized seeds decreases and the bird population becomes two separate populations: one with larger beaks and one with smaller beaks. this demonstrates which of the following? a. sexual selection. b. stabilizing selection. c. directional selection. d. disruptive selection. e. genetic drift.

Explanation:

Disruptive selection favors extreme phenotypes. Here, with medium - sized seeds decreasing, birds with larger and smaller beaks (extreme phenotypes) form separate populations, which is characteristic of disruptive selection. Sexual selection is related to mate - choice, stabilizing selection favors the average phenotype, directional selection favors one extreme, and genetic drift is due to random changes in allele frequencies.

Answer:

D. Disruptive selection.