Cotton-topped tamarins are small primates with tufts of long white hair on their heads. While studying these creatures, researchers noticed that males with longer hair get more opportunities to mate and father more offspring. Which of the following research questions would best test the hypothesis that having longer hair is adaptive in these males?

Question

A. test whether other traits in these males are also adaptive
B. look for evidence of hair in ancestors of tamarins
C. determine if hair length is heritable

Answer 1

The best research question to test the hypothesis that having longer hair is adaptive in male cotton-topped tamarins is:

C. determine if hair length is heritable.

This question helps to establish a genetic basis for the trait, which is crucial for understanding its potential adaptiveness. If hair length is heritable, it could provide an explanation for why longer hair is favored in terms of mating success, and also support the idea that this trait can evolve over generations through natural selection.