GRE Logical Reading: ETS-GRE逻辑单题ETS - F200ZUGOA6340HAEK$

Although it is assumed that peacocks' magnificent tails function essentially to attract peahens, no one knows why it should be magnificent tails that give a competitive advantage in securing mates. One explanation is that peahens are more likely to mate with peacocks with magnificent tails than with peacocks that lack magnificent tails.