Sexual Selection and the Nervous System

he often extreme differences in appearance and behavior of males and females drove Charles Darwin to propose a special kind of evolutionary pressuresexual selection-to explain what natural selection could not (Darwin 1871). The problem, as Darwin saw it, is that males often possess elaborate structures or display energetically costly behaviors that appear to hinder their own survival. These male appurtenances (the peacock's tail is the classic example) are used in courtship of females. Thus the benefits of such