In Cameroon, seedcrackers have either small bills (adapted for feeding on soft sedge seeds) or large bills (adapted for feeding on hard sedge seeds). During competition for scarce resources, these birds primarily feed on the seeds for which they are best adapted. This is an example of ____ selection.
A) stabilizing
B) disruptive
C) frequent
D) directional
E) mutational

Question

​In Cameroon, seedcrackers have either small bills (adapted for feeding on soft sedge seeds) or large bills (adapted for feeding on hard sedge seeds). During competition for scarce resources, these birds primarily feed on the seeds for which they are best adapted. This is an example of ____ selection.
A) ​stabilizing
B) ​disruptive
C) ​frequent
D) ​directional
E) ​mutational

Quizplus · Accepted Answer

Disruptive selection is illustrated here, where two extreme phenotypes (small bills and large bills) are favored over any intermediate phenotype, leading to a split in the population into two distinct groups adapted to different ecological niches.

​In Cameroon, Seedcrackers Have Either Small Bills (Adapted for Feeding

In Cameroon, Seedcrackers Have Either Small Bills (Adapted for Feeding