DISSERTATION RESEARCH: Using Covariance to Test Hypotheses about the Function and Underlying Genetic Control of Multi-component Signals

与其他个体有效沟通的能力对生存和繁殖很重要；然而，人们对产生沟通信号的遗传学知之甚少。这项拟议的项目集中在一种果蝇的求偶过程中使用的声音(听觉)信号。该物种产生的多种听觉信号是复杂的，但它们之间的关系以及它们产生的遗传控制尚未确定。这项拟议的研究融合了动物行为学、进化论和遗传学的方法，以更好地了解动物是如何传递和接收信息的。这可以深入了解哪些信息是从男性传递给女性的，以及这些信息是如何受到基因控制的。考虑到果蝇丰富的遗传知识，以及果蝇和人类共享多少基因，这个物种可以与其他研究系统建立更广泛的联系。此外，该项目的一部分将通过指导两名本科生、在当地一所高中进行外联、出席国家科学会议以及为高中课堂编写教材来扩大公众对信号的遗传学和信息内容的理解。个体之间传输的信号通常是复杂的，包含多个分量。这些组件可能传达相同的信息，在这种情况下，它们预计会协同进化，或者它们可能有不同的消息，这意味着独立进化。了解信号成分如何共同变化以及如何受基因控制，可能有助于深入了解所传达的信息。为了解决这个问题，我们将使用一种新的方法来检测果蝇的声学信号。这个物种有复杂的交配信号，由雄性翅膀振动产生，刺激雌性交配。两个信号成分，脉搏声和嘟嘟声，将被检查表型协方差。歌曲成分之间没有表型协变将支持相应成分包含多个信息的假设。相反，显著的正向协变将支持这样的假设，即各个组成部分包含相同的信息。或者，显著的负协变将支持各个组成部分相互制约的假设。除了表型协方差外，还将使用下一代测序方法通过数量性状基因座(QTL)定位来评估这两个信号成分的遗传结构。信号成分QTL的共位量将决定遗传控制的共性。显著的共定位将意味着共享的基因控制，关联的方向(积极或消极)将表明选择压力如何作用于遗传关联的系统。了解相关信号的遗传控制对于阐明适应性行为特征进化的机制和模拟多成分信号的进化至关重要。

The ability to communicate effectively with other individuals is important for survival and reproduction; however, little is known about the genetics of producing communication signals. The proposed project focuses on sound (auditory) signals used in courtship in a species of fruit fly. The multiple auditory signals produced by this species are complex but their relationships to each other and genetic control of their production have not been determined. The proposed research incorporates methods from animal behavior, evolution, and genetics to better understand how conveying and receiving messages occurs in animals. This can provide insights into what messages are passed from males to females and how these messages are genetically controlled. Given the abundance of genetic knowledge in fruit flies, and how many genes are shared between flies and humans, broader connections can be made from this species to other study systems. In addition, part of the project will extend public understanding of the genetics and information content of signals through mentorship of two undergraduate students, outreach at a local high school, attendance at national scientific conferences, and development of teaching materials for high school classrooms. Signals transmitted between individuals are often complex and contain multiple components. These components may convey the same information, in which case they are expected to evolve in concert, or they may have separate messages, which implies independent evolution. Understanding how signal components co-vary and are genetically controlled may provide insight into the messages conveyed. To address this problem, the acoustic signals of Drosophila sturtevanti will be examined using a novel approach. This species has complex mating signals, generated by male wing vibration, that stimulate females to mate. Two signal components, pulse song and beep song, will be examined for phenotypic covariance. The absence of phenotypic co-variation between the song components will support the hypothesis that the respective components contain multiple messages. In contrast, significant positive co-variation will support the hypothesis that the respective components contain the same message. Alternatively, significant negative co-variation will support the hypothesis that respective components constrain each other. In addition to phenotypic covariance, the genetic architecture of the two signal components will be assessed through quantitative trait loci (QTL) mapping using a next generation sequencing approach. The amount of co-localization of the QTLs for the signal components will determine the commonality of genetic control. Significant co-localization will imply shared genetic control and the direction of association (positive or negative) will indicate how selection pressures act on the genetically linked systems. Understanding the genetic control of associated signals is essential for elucidating mechanisms by which adaptive behavioral traits evolve and for modeling the evolution of multi-component signals.