RIG/CAA: Dispersal, Vocal Convergence and the Maintenance of Vocal Dialects

在鲸鱼、蝙蝠、鸣禽、蜂鸟和鹦鹉等远亲动物群体中，声乐学习能力已经进化。学习发声的能力可能会使更复杂的交流系统的发展成为可能，但代价是大脑代谢昂贵，发育时间延长。研究各种物种学习声音的利弊，将有助于我们了解人类语言是如何以及为什么进化的。学习的一种常见表现形式是地理差异的拼凑模式，称为“方言”。随着时间的推移，方言可能是通过个人从一种方言到另一种方言的有限移动，或者是移民在分散后学习当地的呼叫类型，称为“声音收敛”。之前在哥斯达黎加的亚马逊黄纹鹦鹉中进行的研究表明，在这种鹦鹉中，声音收敛对于维持声音方言很重要。这个项目将记录鸟类何时、如何以及为什么从一种方言迁移到另一种方言学习新的叫声类型。为了更好地监测这些分布广泛的鸟类的活动，新墨西哥州立大学（NMSU）的生物学家和工程师将合作开发利用全球定位系统（GPS）技术的新型遥测方法。幼小的黄枕亚马逊河鼠将被安装上GPS追踪装置，并被跟踪12个月，以记录它们自然的迁徙模式。其他鸟类将从它们的出生方言转移到邻近的方言，以便近距离观察声乐学习并融入新的鸟群。这些实验将为理解该物种的声音趋同所带来的好处提供关键数据。此外，新密西西比州立大学将与世界鹦鹉信托基金会和哥斯达黎加的Conservacíon瓜纳卡斯特地区合作，制定一个综合鹦鹉保护计划，其中包括生物教育和鸟巢保护，以及一个关于鹦鹉筑巢行为的网站，该网站提供鹦鹉巢穴的实时视频。这些活动将为新密歇根州立大学的学生提供培训和指导机会，这是一所为西班牙裔提供土地的大学。

Vocal learning has evolved in such distantly related animal groups as whales, bats, songbirds, hummingbirds and parrots. The ability to learn vocalizations may enable the development of more complex communication systems at the cost of metabolically expensive brains and extended periods of development. Examining the benefits and costs of vocal learning in a range of species will provide insights into how and why human language has evolved. One common manifestation of learning is a patchwork pattern of geographic variation termed 'dialects'. Dialects may be maintained over time either by limited movements of individuals from one dialect to another or by immigrants learning local call types after dispersal, termed 'vocal convergence'. Previous work in the yellow-naped amazon in Costa Rica has suggested that vocal convergence is important for maintaining vocal dialects in this parrot species. This project will document when, how and why birds immigrating from one dialect to another learn new call types. To better monitor movements in these wide-ranging birds, biologists and engineers at New Mexico State University (NMSU) will collaborate to develop novel telemetry methods utilizing Global Positioning System (GPS) technology. Juvenile yellow-naped amazons will be fitted with the GPS tracking devices and followed for 12 months to document natural patterns of dispersal. Other birds will be moved from their natal dialect to a neighboring dialect to allow close observation of vocal learning and integration into new flocks. These experiments will provide critical data for understanding the benefits conveyed by vocal convergence in this species. In addition, NMSU will partner with the World Parrot Trust and the Area de Conservacíon Guanacaste in Costa Rica to develop an integrated parrot conservation program that includes biological education and nest protection and a website on parrot nesting behavior that features live video feeds from parrot nests. These activities will provide training and mentoring opportunities for students at NMSU, a Hispanic-serving land grant university.