Collaborative Research: Testing Alternative Hypotheses for the Maintenance of Behavioral Differences among Populations

该项目将是野外和实验室相结合的延续 研究旨在确定导致 保持棕头燕八哥的发音方言。 研究 将由斯蒂芬·I博士合作进行。罗斯坦 加州大学，圣巴巴拉，和罗伯特C。弗莱舍 夏威夷大学。 他们的研究将包括（1）一个密集的 研究一个大方言中的语音变化，以确定是否 在不同地理尺度上的变化对于通信是重要的， (2)除了一个声音之外， 到目前为止强调，以确定是否所有的发声都在同一个 方式，和（3）广泛的带型、形态学和生化 研究，以确定方言是否在遗传上有差异， 鸟类从一种方言向另一种方言扩散的程度。 这些研究很重要，因为方言在 鸣禽，但我们对它们知之甚少。 一个假设是 方言的维护声称，声音的差异有助于 种群间的生殖隔离。 这一假设归因于 对方言的重要进化意义，甚至表明他们 可能会影响物种形成的速度。 因为对鸟类的研究 在关于新的起源的现代理论的形成中的主要作用 物种，方言研究可能有助于我们理解这一点， 进化生物学的重要方面。 方言也很重要，因为 他们的特点是学习，因此，代表文化 差异 这些鸟类文化差异可能是最好的类比 在动物中，人类特有的文化差异 人口数量。 罗斯坦博士和弗莱舍博士目前收集到的信息 燕八哥并不支持生殖隔离假说。 相反，男性似乎分散和学习新的方言，但在一个 在他们学会新方言之前，他们最初的劣势。 这个过程 与人类行为相似的是，人们从一个国家或一个 在他们了解其他职业之前，他们也处于不利地位 他们的新国家的语言或他们的行话和技术术语， 新职业 最后，这个项目也很重要，因为燕八哥是一个 这是一种对几种濒危鸟类构成威胁的寄生物种。 从项目中获得的基本知识可用于提高 目前正在进行的密集的牛鹂控制计划的有效性 由密歇根州部分地区的联邦和州政府进行， 加州。

This project will be a continuation of combined field and laboratory studies designed to determine the factors responsible for the maintenance of vocal dialects in the brown-headed cowbird. The research will be carried out collaboratively by Dr. Stephen I. Rothstein of the University of California, Santa Barbara, and Dr. Robert C. Fleischer of the University of Hawaii. Their research will include (1) an intensive study of vocal variation within one large dialect, to determine if variation at different geographic scales is important to communication, (2) investigations of additional vocalizations besides the one emphasized so far, to determine if all vocalizations vary in the same manner, and (3) extensive banding, morphological, and biochemical studies, to determine if dialects are differentiated genetically and the degree to which birds disperse from one dialect to another. Such studies are important because dialects are prevalent among songbirds, yet are poorly understood. One hypothesis for the maintenance of dialects asserts that vocal differences facilitate reproductive isolation among populations. This hypothesis attributes major evolutionary significance to dialects and even suggests that they may influence rates of speciation. Because avian studies have played a major role in the formulation of modern theory about the origin of new species, dialect studies may contribute to our understanding of this critical aspect of evolutionary biology. Dialects are also important because the vocal differences that characterize them are learned and, therefore, represent cultural differences. These avian cultural differences may be the best analogs among animals of the cultural differences that characterize human populations. Information that Drs. Rothstein and Fleischer have gathered so far on the cowbird does not support the reproductive-isolation hypothesis. Instead, males seem to disperse and learn new dialects, but are at an initial disadvantage until they learn their new dialect. This process parallels human behavior in that people moving from one country or one profession to another are also at a disadvantage until they learn the language of their new country or the jargon and technical terms of their new profession. Lastly, this project is also important because the cowbird is a parasitic species that is a threat to several endangered bird species. Basic knowledge derived from the project may be used to increase the effectiveness of intensive cowbird-control programs currently being conducted by Federal and State governments in parts of Michigan and California.