DISSERTATION RESEARCH: Character displacement in the morphology and song of two closely-related African barbets

修补匠鸟是一种微小的热带非洲鸟类，它们会唱非常简单的歌。基因变异被认为与那些没有从文化上学会鸣叫的鸟类（如修补匠鸟）的鸣叫变异相似。该项目的目的是研究两个相关物种种群之间鸣叫差异模式的遗传基础，以及身体大小和喙形的差异。据预测，这种分化的发生是为了促进两个物种的共存，这两个物种在生态和行为上如此相似，以至于每个物种的个体可以像与自己物种的个体竞争一样相互竞争。如果两个物种不能识别对方是不同的物种，它们甚至可以相互交配，产生不育的杂种。促进相关物种的识别和共存的生态或行为特征的分化过程被称为特征位移。分析还将解释鸣声、体型和喙形是适应不同环境的可能性，或者是随地理距离随机变化的可能性。虽然在生态学和进化中，角色置换是一个公认的理论，但在自然界中却很少发现这样的例子。这项研究将首次明确地证明鸟类鸣叫中的特征位移，并为身体大小和喙形的平行变化提供支持。该项目涉及与乌干达和喀麦隆的保护组织合作，雇用它们的工作人员以及乌干达的大学本科生作为实地助理，从而帮助发展中国家科学家的发展。

Tinkerbirds are tiny tropical African birds that sing very simple songs. Genetic variation is thought to parallel song variation among populations of birds that do not learn their songs culturally, such as tinkerbirds. The aim of this project is to examine the genetic basis of a pattern of divergence in song between populations of two related species, as well as divergence in body size and beak shape. Such divergence is predicted to occur in order to facilitate coexistence of two species that are so similar in ecology and behavior that individuals of each species could compete with each other as they would with individuals of their own species. If two species fail to recognize each other as different species, they could even mate with each other and produce infertile hybrids. The process of divergence in ecological or behavioral traits that facilitates recognition and coexistence of related species is known as character displacement. Analyses will also account for the possibility that song, body size, and beak shape are adapted to differences in the environment, or vary randomly over geographic distances.While character displacement is a well-established theory in ecology and evolution, few examples have been found in nature. This study will provide the first unambiguous demonstration of character displacement in bird song, and provide support for it with parallel shifts in body size and beak shape. The project involves working with conservation organizations in Uganda and Cameroon, employing their staff as well as Ugandan university undergraduates as field assistants, thus helping the development of scientists in developing countries.