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

叮当鸟是一种热带非洲小鸟，会唱非常简单的歌。遗传变异被认为是与在文化上不学习歌唱的鸟类种群之间的歌声变异平行的，比如叮当鸟。这个项目的目的是研究两个相关物种的种群之间歌唱模式差异的遗传基础，以及身体大小和喙形状的差异。据预测，这种分化是为了促进两个在生态和行为上如此相似的物种的共存，以便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。如果两个物种无法将彼此识别为不同的物种，它们甚至可能相互交配，产生不育的杂交后代。在生态或行为特征上的差异促进了相关物种的识别和共存，这一过程称为性格置换。分析还将解释这样一种可能性，即歌声、体型和喙的形状可能是适应环境的差异，或者是随地理距离随机变化的。虽然角色置换是生态学和进化论中一个久负盛名的理论，但在自然界中很少发现这样的例子。这项研究将首次明确地证明鸟鸣中的角色移位，并通过身体大小和喙形状的平行移位为其提供支持。该项目涉及与乌干达和喀麦隆的保护组织合作，雇用他们的工作人员以及乌干达大学本科生作为实地助理，从而帮助发展中国家的科学家发展。

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.