Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Seewiesen, Germany.
School of Biological Sciences, Monash University, Clayton, Vic., Australia.
J Evol Biol. 2020 Nov;33(11):1543-1557. doi: 10.1111/jeb.13690. Epub 2020 Aug 30.
Psittaciformes (parrots, cockatoos and lorikeets) comprise one of the most colourful clades of birds. Their unique pigments and safe cavity nesting habits are two potential explanations for their colourful character. However, plumage colour varies substantially between parrot species and sometimes also between males and females of the same species. Here, we use comparative analyses to evaluate what factors correlate with colour elaboration, colour diversity and sexual dichromatism. Specifically, we test the association between different aspects of parrot colouration and (a) the intensity of sexual selection and social interactions, (b) variation along the slow-fast life-history continuum and (c) climatic variation. We show that larger species and species that live in warm environments display more elaborated colours, yet smaller species have higher levels of sexual dichromatism. Larger parrots tend to have darker and more blue and red colours. Parrots that live in wetter environments are darker and redder, whereas species inhabiting warm regions have more blue plumage colours. In general, each of the variables we considered explain small to moderate amounts of variation in parrot colouration (up to 15%). Our data suggest that sexual selection may be acting more strongly on males in small, short-lived parrots leading to sexual dichromatism. More elaborate colouration in both males and females of the larger, long-lived species with slow tropical life histories suggests that mutual mate choice, social selection and reduced selection for crypsis may be important in these species, as has been shown for passerines.
凤头鹦鹉目（鹦鹉、凤头鹦鹉和吸蜜鹦鹉）是鸟类中最具色彩的类群之一。它们独特的色素和安全的洞穴筑巢习性是其多彩特征的两个潜在解释。然而，鹦鹉物种之间的羽毛颜色差异很大，有时甚至同一物种的雄性和雌性之间也存在差异。在这里，我们使用比较分析来评估哪些因素与颜色的精细化、颜色的多样性和性别二态性相关。具体来说，我们测试了鹦鹉颜色的不同方面与（a）性选择和社会互动的强度、（b）沿慢-快生活史连续体的变化以及（c）气候变化之间的关联。我们表明，体型较大的物种和生活在温暖环境中的物种的颜色更加精细化，但体型较小的物种的性别二态性更高。较大的鹦鹉往往具有更深色、更多蓝色和红色的颜色。生活在潮湿环境中的鹦鹉颜色更深、更红，而生活在温暖地区的物种则具有更多的蓝色羽毛颜色。总的来说，我们考虑的每个变量都可以解释鹦鹉颜色变化的小到中等程度（高达 15%）。我们的数据表明，性选择可能在体型较小、寿命较短的雄性鹦鹉中更为强烈，导致性别二态性。体型较大、寿命较长、生活在热带地区的物种中，雄性和雌性都具有更精细化的颜色，这表明在这些物种中，相互配偶选择、社会选择和对伪装的选择减少可能很重要，就像雀形目鸟类一样。
