Plumage Coloration of the Blue Grosbeak has no Dual Function: A Test of the Armament—Ornament Model of Sexual Selection

[摘要] Abstract. Although plumage coloration has been widely used as a model in studies of the evolution of signaling, the role of plumage in intrasexual communication has been less studied, especially in cases of the structural plumage color. The aim of our study was to use choice trials and plumage manipulation to test whether or not the structural blue color of the male Blue Grosbeak (Passerina caerulea) works as a signal of social status. Additionally, we tested whether or not females exploit signals used in aggression between males. If they do, it suggests that plumage coloration is also used in mate choice. In 2007, we captured males and females from two different populations. We performed two choice experiments by manipulating plumage color: (1) a status-signaling experiment, in which a male had to choose one of two other males, and (2) a mate-choice experiment, in which a female had to choose one of two males. Males clearly foraged near less blue birds during their first encounter and on the first day. H...

[学科分类] 动物科学

[关键词] armament—ornament model;Blue Grosbeak;male—male competition;mate choice;Passerina caerulea;status-signaling hypothesis;structural plumage color