| extremely loud mating songs at close range in white bellbirds. | sexual selection in many animal species favors the evolution of elaborate courtship traits. such traits might help signalers convey, and receivers discern, information about signaler quality; or they might be favored by perceptual or aesthetic preferences for elaborateness or beauty [1-3]. under either scenario we expect sexual trait elaboration to be countered by proximate constraints rooted in animals' morphology, physiology and phylogenetic history [3,4]. during expeditions to a montane rainf ... | 2019 | 31639347 |