绿背姬鹟鸣声和羽饰延迟成熟及其适应性研究

Many animals can display and perceive more than one signaling trait in sexual communication. Song and plumage of male songbirds are well-known sexually seclected trait and play a major role in female prefenence and male-male interaction. Only few researches have examined sexual secection on plumage and song simutaneously within a population, and the processes affecting the relative expression of song and plumage are poorly understood.Green-backed flycatcher (Ficedula elisae) is a small,only breeding in North China, passerine bird in which delayed maturation on both song and plumage, and provides ideal model for comparing age-related difference in male plumage and song-based sexual signals. In this project, we use Green-backed flycatcher as a model, A) to compare the song and plumage traits in the second year male (SY) and after second-year male(ASY), and detect the interactions of song and plumage; B) to check the ratio of SY male present DPM and DSM, and whether DPM occurs also in female; C) to test whether the male can identify the SY and ASY on the basis of the song and plumage signal, and to test the relative hypothesis; D) to analyze the male quality on the basis of physiology parameters, in addition, to compare the male quality of SY and ASY; E)and evalute the relationship between sexual selection and different song and plumage compontent. Our work will reveal the age-related difference of signal and interaction, and examine sexual selection on traits of multimodel signal simultaneously in same breeding population, and be of benefit to understand of sexual signalling system.

羽饰和鸣唱是鸟类重要的性选择信号，在同性和异性间通讯中起重要的作用。已有研究多关注单一信号对性选择的影响，对雄鸟同时展示出来的羽饰和鸣唱信号在性选择中的作用研究很少。绿背姬鹟存在鸣唱（DSM）和羽饰延迟成熟(DPM)现象，其繁殖成效也迥异于已报道的其他延迟成熟鸟类,其基于年龄的羽饰和鸣唱的性状分离现象，为探讨多模态信号在性选择中的作用提供了理想模型。 本项目以绿背姬鹟为模型动物，开展如下工作：1）比较第二年（SY）和第二年以上（ASY）雄鸟羽色和鸣唱差异，并分析两种信号的相关性；2）检测雄性DPM和DSM的比率以及雌性是否具DPM；3)分析绿背姬鹟对SY和ASY雄鸟鸣唱、羽饰信号差异的识别能力；4）建立雄性质量评价标准，比较SY和ASY雄性质量差异；5）分析不同的羽饰和鸣唱特征（组分）与性选择和适合度的相关性。本项目在DPM和DSM研究的基础上，探讨多模态信号与性选择、适合度的相关性。

羽饰和鸣唱是鸟类重要的性选择信号，在同性和异性间通讯中起重要的作用。绿背姬鹟该物种存在鸣唱（DSM）和羽饰延迟成熟(DPM)现象，即存在年龄的羽饰和鸣唱的性状分离现象，且该物种的独立物种地位一直争论较大。本项目对绿背姬鹟分类地位、鸣声和羽饰延迟成熟及机制的研究，取得了如下成果：1）通过羽饰、鸣声和DNA分析，提出绿背姬鹟为独立的物种，该结论目前已经被国内外分类论著广泛接受。2）绿背姬鹟的鸣唱包含了白眉姬鹟的音素，白眉姬鹟对同种个体的鸣唱与绿背姬鹟鸣唱反应无显著差异；对绿背姬鹟的鸣唱反应虽强于对对照组的反应，但未达到显著水平（P=0.09）。；3）绿背姬鹟鸣唱具有功能分化，回放诱发鸣唱的句子时长显著缩短(F=55.534，P＜0.001，repeated measures ANOVA)、音素数目显著减少（F=50.856，P＜0.001，repeated measures ANOVA），起始音节组更多用于保卫领域；4）绿背姬鹟SY和ASY的鸣唱语句在音节、句法和句型基本相似，句子的时间、频率特征亦无差异，但SY雄鸟起始音节组结构类型数目显著多于ASY雄鸟（T=6.358，P＜0.001，independent sample t test)，绿背姬鹟通过鸣唱区分SY与ASY的入侵者(t=-3.212, P=0.002)，支持 “地位信号假说”；5）绿背姬鹟ASY雄鸟对ASY雄鸟的攻击强度显著高于对SY雄鸟的攻击强度（t=3.48, df=30, p=0.002）和对雌鸟的攻击强度（t=3.98, df=30, p=0.0004），而对SY雄鸟的攻击强度和对雌鸟的攻击强度没有显著差异（t=0.28, df=30, p=0.781），绿背姬鹟SY雄鸟对这三种“入侵者”的攻击强度则没有显著差异（F=0.593, df=7.34, p=0.577），攻击强度差异的分析结果符合模仿雌鸟假说的预测，不符合地位信号假说的预测。ASY和SY鸣声和羽饰差异应当是生活史策略中视觉和听觉信号的互补和替代。