CAREER: Flexibility, constraints, and selection in repeated ear loss and regain in toads

大多数青蛙和蟾蜍通过发声来交流，雌性通常用听觉来定位配偶。尽管鼓室耳对于在空气中听到声音是多么重要，但青蛙和蟾蜍的外耳和中耳结构已经多次丧失和恢复。该项目整合了解剖学、生理学、发育和系统发育分析，以研究耳结构的独立得失。将耳朵形态与听力能力联系起来将揭示新的听力机制，并将表征各种解剖特征对低、高音声音的听觉成本和收益。由于耳朵结构的发育与其他头骨特征的发育有关，因此该项目将确定伴随耳朵结构变化的颅骨大小和形状的变化。此外，发育分析将确定导致外耳和中耳结构丧失的特定遗传和细胞变化，这是一种耳部缺陷，是人类耳聋的常见原因。颅骨特征的综合分析将评估颅骨的相关变化是否促进了耳朵结构的多样性，这些数据可在Digimorph （http://www.digimorph.org/）和CSU数字资源库（http://lib.colostate.edu/repository/）上公开获得。本提案中的研究包括更好地教育公众和大学生关于听力、生物多样性和保护的自然机会。在美国，这一提议将被整合到本科课程中，作为一种新的实验室方法的一部分，教学生进行和解释统计分析。此外，美国本科生将参与研究工作，并参与开发一个关于青蛙的双语博物馆展览，该展览将在一个或多个美国科学博物馆展出。在道路建设和资源开采可能对厄瓜多尔野生动物产生重大影响的关键时刻，厄瓜多尔蟾蜍繁殖计划和相关的厄瓜多尔博物馆展览将有助于两栖动物保护。

Most frogs and toads vocalize to communicate, and females typically use hearing to locate mates. Despite how essential tympanic ears are for hearing sound in air, outer and middle ear structures have been lost and regained many times in frogs and toads. This project integrates anatomy, physiology, development, and phylogenetic analyses to investigate the independent gains and losses of ear structures. Relating ear morphology to hearing ability will reveal novel mechanisms of hearing and will characterize the costs and benefits of various anatomical features for hearing low and high pitch sounds. Because the development of ear structures is linked to the development of other skull features, this project will identify changes in the size and shape of skull bones that accompany changes in ear structures. Moreover, developmental analyses will determine specific genetic and cellular changes that cause the loss of outer and middle ear structures, a type of ear defect that is a common cause of human deafness.Integrative analyses of skull features will assess whether associated changes in skulls facilitate the diversity of ear structures, with data publicly available at Digimorph (http://www.digimorph.org/) and the CSU Digital Repository (http://lib.colostate.edu/repository/). The research in this proposal includes natural opportunities to better educate the general public and university students about hearing, biodiversity, and conservation. Within the US, this proposal will be integrated into undergraduate classes as part of a new laboratory approach to teach students to conduct and interpret statistical analyses. In addition, US undergraduates will participate in the research efforts and participate in developing a bilingual museum exhibition about frogs that will be displayed at one or more US science museums. The Ecuadorian toad breeding program and a related Ecuadorian museum exhibition will contribute to amphibian conservation at a key moment when road-building and resource extraction threaten to have major impacts on wildlife in Ecuador.