In Eurasia, two closely related species of rock nuthatches (small birds that forage for insects and spiders on bare, rocky ground) occur either separately, or in zones of sympatry. Individuals of both species that exist in the former situation, with no interspecies competition, have bills that are similar in length. But in their zone of sympatry in Iran, one species has a longer bill than it has elsewhere and the other species has a shorter bill. This is an example of _______ competition that has resulted in _______.
A) exploitation; resource partitioning
B) exploitation; character displacement
C) interference; resource partitioning
D) interference; character displacement
E) None of the above

Question

Quizplus · Accepted Answer

This scenario describes character displacement, where species evolve distinct traits to minimize competition when they coexist (sympatry). The bill length differences in sympatry indicate adaptation to reduce competition for resources, which is a form of exploitation competition.

In Eurasia, Two Closely Related Species of Rock Nuthatches (Small