Collaborative Research: Sexual Selection on Male Ornamental Traits in Birds

合作研究：雄性观赏动物的性选择雄性动物通常具有观赏性的特征，如长长的尾巴和鲜艳的颜色，它们用这些来吸引配偶。 这些装饰品可能是女性选择或男性之间的竞争所青睐的。 女性的选择很可能比男性与男性的竞争对不同的装饰品起作用，特别是当一些装饰品比其他装饰品更能揭示男性的品质时。 例如，在具有类胡萝卜素（红色、黄色）和黑色素（黑色、棕色）装饰物的物种中，雌性似乎经常将其配偶选择集中在类胡萝卜素装饰物上，这通常被认为是比黑色素装饰物更好的男性状况指标。 令人惊讶的是，我们发现了两个种群的一夫一妻制鸟类，共同黄喉，其中一个种群（纽约）的雄性繁殖成功与类胡萝卜素为基础的装饰品（黄色围兜）的大小有关，另一个种群（威斯康星州）的黑色素为基础的装饰品（黑色面膜）。 本研究将探讨两个族群对每一种羽毛装饰的性选择，本研究将：1）利用鸟舍实验来确定哪些装饰物是雌性选择和雄性-雄性竞争所青睐的; 2）确定族群之间的差异是否是由对不同装饰物的不同选择机制所造成的。 普通的黄喉鹦鹉是少数几个研究人员能够识别大多数幼崽（包括额外配对的幼崽）的父系的物种之一，因此，可以估计出雄性装饰物的全部选择力。该项目的更广泛影响之一将是促进对学生进行合作研究的培训，这将使他们对如何开展科学有更好的认识。为了促进这种培训，PI将交换学生之间的两个机构（一个是小型本科院校，另一个是大型研究生课程），每年都为现场和实验室的项目组成部分。

Collaborative Research: Sexual Selection on Male OrnamentsPI: Peter Dunn, Corey Freeman-GallantMales often possess ornamental traits such as long tails and bright colors that they use to attract mates. These ornaments may be favored by female choice or male-male competition. Female choice is likely to act on different ornaments than male-male competition, particularly when some ornaments are more revealing of male quality than others. For example, in species with both carotenoid (red, yellow) and melanin (black, brown)-based ornaments, it appears that females often focus their mate choice on the carotenoid-based ornaments, which are generally considered to be better indicators of male condition than ornaments with melanin pigments. Surprisingly, we have discovered two populations of a monogamous bird, the common yellowthroat, in which male reproductive success is related to the size of a carotenoid-based ornament (yellow bib) in one population (New York) and a melanin-based ornament (black facial mask) in another population (Wisconsin). Our study will examine sexual selection on each plumage ornament in both populations.This study will 1) use aviary experiments to identify which ornaments are favored by female choice and male-male competition, and 2) determine if the differences between populations are caused by different mechanisms of selection operating on different ornaments. Common yellowthroats are one of only a handful of species in which researchers have been able to identify the sires of most young, including extra-pair young, and, as a consequence, make an estimate of the full force of selection on male ornaments. One of the broader impacts of this project will be to foster training of students in collaborative research, which will give them a better perspective on how science is conducted. To facilitate this training, the PIs will exchange students between their two institutions (one a small undergraduate institution, the other a large graduate program) each year for both the field and laboratory components of the project.