It is difficult to measure the fitness costs of inbreeding because the frequency of inbreeding is usually low. However, Brown and Brown (1998), during a long-term study of the Mexican jay (Aphelocoma ultramarina), found that
A) fewer of the inbred nestlings survived to the next year when compared with outbred nestlings.
B) inbred pairs appeared to experience a higher rate of hatching failure.
C) the brood sizes of inbred pairs were smaller than those of outbred pairs.
D) all of the above.

Question

Quizplus · Accepted Answer

Brown and Brown (1998) found that inbred Mexican jays had lower survival rates, higher hatching failure rates, and smaller brood sizes compared to outbred individuals, indicating significant fitness costs of inbreeding.

It Is Difficult to Measure the Fitness Costs of Inbreeding