DISSERTATION RESEARCH: The Cardiac Response as a Measure of Song Perception in the Song Sparrow Melospiza melodia

雄性鸣鸟在互动时会使用各种特殊的鸣叫行为。这些行为被认为在男性与男性之间的竞争中起到了信号的作用，但对于许多行为来说，仍然不清楚这些显示传递的是什么信息。研究雄鸟对这些行为的感知和反应是理解歌声在这一背景下如何发挥作用的关键。雄鸟对歌声的感知通常是通过测量对歌声回放的攻击性反应来测试的。这类测试的结果很难解释，因为对最具威胁性的刺激或最不具威胁性的刺激可能会给出最强烈的攻击性反应。这个项目将使用歌曲回放引起的心脏反应(心率变化)作为雄性鸣禽对歌曲和其他刺激感知的替代测量。具体地说，这项措施将被用来测试对低幅度歌唱的感知，这是一种被认为具有高度攻击性的歌唱行为，并确定鸟类在它们的领地上可以感知到柔和歌声的距离。心脏测量已被证明对检测各种物种和环境中的信号感知有用，但尚未被应用于鸟类攻击性信号感知的假说。更广泛的影响：该项目的更广泛的影响包括促进女性在科学领域的专业发展，并为本科生提供获得研究技能和经验的机会。许多本科生和毕业生在这个项目中得到了指导，其中许多人后来进入了动物行为方面的专业生涯。

Male songbirds use a variety of specialized singing behaviors when they interact. These behaviors are presumed to function as signals in male-male competition, yet for many behaviors it remains unclear what information the display is signaling. Examining how male birds perceive and respond to these behaviors is key to understanding how song functions in this context. Song perception by male birds is usually tested by measuring aggressive responses to song playback. The results of such tests are difficult to interpret, because the strongest aggressive response may be given to either the most threatening stimuli or to the least threatening stimuli. This project will use the cardiac response (change in heart rate) evoked by song playback as an alternative measure of the perception of song and other stimuli by male song sparrows. Specifically, this measure will be used to test the perception of low-amplitude song ('soft song'), a singing behavior that is thought to be highly aggressive, and to determine the distance over which soft song can be perceived by birds on their territories. Cardiac measures have proven useful for examining signal perception in a variety of species and contexts, but have not been applied to hypotheses about aggressive signal perception in birds. Broader Impacts: The broader impacts of this project include promoting the professional development of women in science, and providing opportunities for undergraduate students to gain research skills and experience. Numerous undergraduates and graduates have been mentored in this program, many of whom have gone on to professional careers in animal behavior.