Neuroendocrine Basis of Behavioral Polymorphism

白喉麻雀引起了行为生物学家的极大兴趣，因为它有两种“变种”或类型，它们有不同的社会行为。在野外和实验室环境中进行的数十项行为研究已经确定，冠上有白色条纹的个体往往更具攻击性，而有褐色条纹的鸟类则表现出更多的亲代关怀。通过本项目的研究，将揭示白鸟比棕鸟更具攻击性的神经化学原因。由于类固醇激素睾酮在白种雄性中高于棕褐色雄性，因此研究睾酮可能改变攻击性的生物学途径，从而导致不同种类之间的行为差异是本项目的基本特征。PI使用的方法是强大的，因为它将全面检查同一个体的行为和神经化学，从而能够详细研究个体差异。因为攻击行为的生物学基础在大多数脊椎动物中是相似的，这些研究的结果将有助于更好地理解包括人类在内的成千上万物种的攻击行为的神经化学基础。研究生将接受行为生物学、神经科学和分子生物学的培训，因此将为整合这三个领域的职业做好充分的准备。该项目还将指导几名本科生，并鼓励他们在国家会议和发表的期刊文章中展示他们的发现。

The white-throated sparrow has generated a great deal of interest among behavioral biologists because it occurs in two "morphs", or types, that have different social behavior. Dozens of behavioral studies, conducted in both field and laboratory settings, have established that individuals with a white stripe on the crown tend to be more aggressive, whereas birds with a tan stripe exhibit more parental care. By conducting the studies in this project, the neurochemical reasons why white birds are more aggressive than tan birds will be revealed. Because the steroid hormone testosterone is higher in white than tan males, investigating the biological ways in which testosterone may alter aggression and thus cause behavioral differences between morphs is an essential feature of this project. The approach used by the PI is powerful because it will comprehensively examine both behavior and neurochemistry in the same individuals, thus enabling detailed study of individual variation. Because the biological basis of aggressive behavior is similar in most vertebrate animals, the results from these studies will facilitated a better understanding of the neurochemical underpinnings for aggression in tens of thousands of species, including humans. A graduate student will receive training in behavioral biology, neuroscience, and molecular biology, and will thus be well prepared for career that integrates all three fields. The PI will also mentor several undergraduate students, and will encourage them to present their findings at national meetings and in published journal articles.