DISSERTATION RESEARCH: Functional Significance of Elaborate Plumage Characters when Expressed in both Sexes: A Case Study of the Turquoise-Browed Motmot (Eumomota superciliosa)

论文研究：两性羽毛特征的功能意义：绿松石眉山雀 (Eumomota superciliosa) 的案例研究

• 批准号: 0206584
• 负责人: Stephen Emlen
• 金额: --
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-04-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206584&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Functional; Significance; Elaborate

Functional significance of elaborate plumage characters when expressed in both sexes: a case study of the turquoise-browed motmot (Eumomota superciliosa)Stephen T. Emlen - ProfessorTroy G. Murphy - Graduate StudentElaborate plumage is generally found in sexually dimorphic species of birds and is thought to be the product of sexual selection. When found in both males and females, this presents a paradox because females generally do not compete for access to males. Such elaborate, monomorphic characters may be products of natural selection acting equally on the sexes, or they may be products of mutual sexual selection acting equally on the sexes. The latter may occur in cases where both males and females compete for access to mates.This project is designed to test the adaptive function of extreme avian plumage elaboration when expressed equally in each sex. The focal species is the monomorphic and brilliantly plumed turquoise-browed motmot (Coraciiformes: Momotidae: Eumomota superciliosa) which breeds at colonial breeding grounds in Northern Yucatan, Mexico. Both males and females of this socially monogamous species have a number of equally exaggerated plumage characters, most notably of which is an elongate tail that terminates in large oval-shaped rackets that extend far below the body of the bird. This investigation will address whether the elaborate racket-tipped tail functions as a sexual signal used in competition for mates, or if it functions in a utilitarian context driven by natural selection. Five hypotheses for the function of the elaborate plumage will be tested using behavioral observations and experimental manipulations. Information gathered from this study will increase the scientific knowledge on the selective forces that maintain elaborate characters in monomorphic species.

精致的羽毛特征在两性中表达时的功能意义：以蓝绿色眉毛的土鹦鹉为例研究（Eumomota superciliosa）。精致的羽毛通常存在于两性异型的鸟类物种中，被认为是性选择的产物。当在男性和女性身上都发现时，这就出现了一个悖论，因为女性通常不会为获得男性的机会而竞争。这种精致的单态特征可能是自然选择对两性平等作用的产物，也可能是两性相互性别选择的产物。后者可能发生在雄性和雌性都为获得配偶而竞争的情况下。本项目旨在测试鸟类在性别平等的情况下，羽毛精细程度的适应功能。焦点物种是单形的，有着鲜艳的绿松石色羽毛的土苔鼠（coraciformes: Momotidae: Eumomota superciliosa），它们在墨西哥尤卡坦半岛北部的殖民地繁殖地繁殖。这种社会一夫一妻制物种的雄性和雌性都有许多同样夸张的羽毛特征，其中最引人注目的是一条长长的尾巴，末端是一个巨大的椭圆形球拍，延伸到鸟的身体下方。这项研究将探讨这种精致的球拍状尾巴是作为配偶竞争中的性信号，还是在自然选择的功利背景下发挥作用。我们将通过行为观察和实验操作来验证五种关于精致羽毛功能的假设。从这项研究中收集的信息将增加对维持单态物种精细性状的选择力的科学知识。