Beak color dynamically signals changes in fasting status and parasite loads in king penguins

Dynamic ornamental signals that vary over minutes, hours or weeks can yield continuous information on individual condition (e.g., energy reserves or immune status), and may therefore be under strong social and/or sexual selection. In vertebrates, the coloration of the integument is often viewed as a dynamic ornament, which in birds can be apparent in the beak. King penguins (Aptenodytes patagonicus) are monomorphic seabirds that possess conspicuous yellow–orange (YO) and ultraviolet (UV) beak spots that are used by both males and females in mate choice. We studied the dynamicity of beak spot sexual traits, and to what extent they reflected changes in individual condition in fasting king penguins and in penguins treated with an anti-parasitic drug. We also describe the maturation of this colorful ornament during the yearly catastrophic moult. On a time-scale of days to weeks, beak spot coloration changed in response to fasting and experimental changes in parasite load. Beak spot UV brigh...随分钟、小时乃至周度尺度动态变化的装饰性信号，可提供个体状态（如能量储备或免疫状态）的连续相关信息，因此这类信号可能受到强烈的社会选择与/或性选择的作用。在脊椎动物中，体表色彩常被视为一类动态装饰结构，而在鸟类中，这类装饰可直观体现在喙部。王企鹅（Aptenodytes patagonicus）为单态型海鸟，其喙部带有醒目的黄橙色（yellow–orange, YO）与紫外（ultraviolet, UV）斑点，雌雄个体均会利用这类斑点进行配偶选择。本研究探究了王企鹅喙部斑点性征的动态变化特征，以及在禁食的王企鹅与经抗寄生虫药物处理的王企鹅中，这类斑点在多大程度上能够反映个体状态的变化。本研究同时描述了该彩色装饰结构在年度灾难性换羽过程中的成熟变化。在数天至数周的时间尺度下，王企鹅喙部斑点的色彩会随禁食处理与实验性寄生虫负荷变化而发生改变。喙部斑点的紫外（UV）亮度……