Sound Fields and Mate Choice

9723521 Bradbury许多动物发声系统的适应性设计受到选择的强烈影响，以增加呼叫幅度并将这些声音有效地投射到预期接收者的方向。在某些系统中，特定的结构对音量和方向性都有深远的影响。 在许多不同脊椎动物群体的发声系统中作为附属器官出现的一种这样的结构是可充气气囊。虽然这种适应显然是这些系统的一个重要特征，但人们对气囊如何影响音量和方向性知之甚少。 本研究利用多声道录音技术，以几种列金松鸡为研究对象，探讨其发声幅度、方向性与声囊形状和数量的关系。我们之所以选择松鸡，是因为不同物种的气囊位置和操作有着不同程度的有趣变化。 有些松鸡有成对的外部气囊。初步证据表明，鼠尾草松鸡男性可能会使用他们的双囊系统，以光束的某些组件，他们的交配显示对女性无论男性的相对方向。 这些数据也将被用来重新审视的作用，振幅在择偶的雌性鼠尾草松鸡。 鼠尾草松鸡leks是一个最好的研究系统中，女性选择配偶的基础上，男性表型，呼叫幅度是唯一的参数，一直保持抵抗适当的测量。 我们现在有办法进行这些测量并完成分析。 我们的希望是，这项比较研究将产生的模型，可以应用到其他群体的声囊功能，更广泛地说，有助于我们理解的重要性，幅度和方向性的女性选择偏向交配系统。

9723521 Bradbury The adaptive design of many animal sound production systems is strongly influenced by selection for increased call amplitude and efficient projection of those sounds in the direction of intended recipients. In some systems, specific structures have profound effects on both volume and directionality. One such structure which appears as an accessory organ in the sound production systems of many diverse vertebrate groups is an inflatable air sac. While this adaptation is clearly an important feature of these systems, very little is known about how air sacs affect sound volume and directionality. Using newly developed multitrack recording techniques, this study will focus on several species of lekking grouse to clarify the relationship between display call amplitude, the directionality of the call, and the shape and number of vocal sacs. We have chosen grouse because of the degree of interesting variations in air sac position and operation in the different species. Some grouse have paired external air sacs. Preliminary evidence suggests that sage grouse males may use their two-sac system to beam certain components of their mating displays toward females regardless of the males' relative orientation. These data will also be used to re-examine the role of amplitude in mate choice of female sage grouse. Sage grouse leks are one of the best studied systems in which females choose mates solely on the basis of male phenotype; call amplitude is the only parameter which has remained resistant to proper measurement. We now have the means to make these measurements and complete the analysis. Our hope is that this comparative study will generate models that can be applied to vocal sac function in other groups and, more broadly, contribute to our understanding of the importance of amplitude and directionality in female choice biased mating systems.