Rosenthal and Evans used playbacks of video animations to show that females did not exhibit a preference between a swordless male and a sworded male if the total body length of the two were equal.
Much of the research in sexual selection in the last two decades has examined how a female’s preference that does not influence her immediate reproductive success can still evolve if it is genetically correlated with another character under direct selection.
Two hypotheses for female preference evolution—runaway sexual selection and good genes selection—state that preferences evolve indirectly because they are genetically correlated with male traits that are under direct selection; that is, the preferences themselves are not under direct selection.
State 声明。在引述别人的观点时，如果不能完全同意，使用state 比show更加中立些。
Studies of receiver biases suggest that such analogies might not be broadly applicable.
Burley argued that the preference for red beaks is adaptive because it indicates male health, and this preference is then transferred to leg-band color.
According to the anti-monotony hypothesis, habituation plays an important role in the evolution of complex vocalizations in songbirds: Increased song complexity reduces habituation of neighboring males and courting females.
Previous studies of acoustic and bioluminescent interactions had emphasized potential advantages to group-signaling organization, such as minimizing predation, preserving species-specific signal characters, or increasing the attractiveness of the group.