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


ANSWER: b

Biology & Microbiology

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A. receives, generates, and conducts electrical signals throughout the body B. is rich in extracellular matrix C. generates force that facilitates movement D. forms continuous sheets that line body surfaces E. is composed of cells held together by tight junctions

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