[Campbell Biology P.547] Based on the text's example of black-bellied seedcracker finches, w... | Practice Question

Based on the text's example of black-bellied seedcracker finches, why do birds with intermediate-sized bills have lower relative fitness?

  • A: They cannot find any type of seed.
  • B: They are inefficient at cracking both soft and hard seeds.
  • C: They are more susceptible to predation.
  • D: They compete too much with both small-billed and large-billed birds.

Explanation

The text states: 'It appears that birds with intermediate-sized bills are relatively inefficient at cracking both types of seeds and thus have lower relative fitness.' This directly answers the question.