Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary.
PLoS One. 2011;6(8):e23201. doi: 10.1371/journal.pone.0023201. Epub 2011 Aug 10.
In complex sexual signaling systems such as plumage color, developmental or genetic links may occur among seemingly distinct traits. However, the interrelations of such traits and the functional significance of their integration rarely have been examined.
METHODOLOGY/PRINCIPAL FINDINGS: We investigated the parallel variation of two reflectance descriptors (brightness and UV chroma) across depigmented and melanized plumage areas of collared flycatchers (Ficedula albicollis), and the possible role of integrated color signals in mate acquisition. We found moderate integration in brightness and UV chroma across the plumage, with similar correlation structures in the two sexes despite the strong sexual dichromatism. Patterns of parallel color change across the plumage were largely unrelated to ornamental white patch sizes, but they all showed strong assortative mating between the sexes. Comparing different types of assortative mating patterns for individual spectral variables suggested a distinct role for plumage-level color axes in mate acquisition.
CONCLUSIONS/SIGNIFICANCE: Our results indicate that the plumage-level, parallel variation of coloration might play a role in mate acquisition. This study underlines the importance of considering potential developmental and functional integration among apparently different ornaments in studies of sexual selection.
在复杂的性信号系统中，如羽毛颜色，看似不同的特征之间可能存在发育或遗传联系。然而，这些特征之间的相互关系及其整合的功能意义很少被研究。
方法/主要发现：我们调查了领雀嘴鹎（Ficedula albicollis）褪色和黑化羽毛区域的两个反射率描述符（亮度和 UV 色度）的平行变化，并研究了整合的颜色信号在配偶获取中的可能作用。我们发现，尽管存在强烈的两性二色性，但亮度和 UV 色度在羽毛中具有中等程度的整合，两性之间具有相似的相关结构。羽毛上颜色的平行变化模式与装饰性白斑的大小基本无关，但两性之间存在强烈的选择性交配。比较个体光谱变量的不同类型的选择性交配模式表明，在配偶获取中，羽级颜色轴可能具有独特的作用。
结论/意义：我们的结果表明，颜色的羽级平行变化可能在配偶获取中起作用。这项研究强调了在研究性选择时，考虑到看似不同的装饰物之间潜在的发育和功能整合的重要性。
