CAREER: Performance and Fitness Consequences of Insect Ornaments

研究方向：昆虫装饰物的性能和适应性结果南达科他州大学无性选择在很大程度上决定了动物的形态多样性，通常以雄性装饰物展示的形式表现出来。性选择理论指出，这些展示特征并非没有代价，因此自然选择会抵消这些展示特征及其代价。柄眼蝇提供了理想的模型系统来测试与雄性装饰有关的成本和权衡。这个特殊家族的所有物种都表现出夸张的头部形态，眼睛和触角在长柄的末端移位，眼睛跨度的种间变异可以超过十倍。此外，所有现有证据都表明，眼柄是雄性竞争和雌性选择的关键性信号。本研究将检验长眼柄对长眼蝇的飞行性能和存活率的影响，以评估这些影响是否与性选择的影响背道而驰。为了实现这一目标，PI将整合来自三个不同研究途径的信息。首先，为了建立形态学和飞行能力之间的联系，我们将在单个物种——绿藓藻（Cyrtodiopsis dalmanni）中测量眼展和运动能力的变化，以测试第二性征和飞行适应之间的权衡。在这项研究中，dalmanni C.被双向选择为增加和减少眼距的品系将用于增加该物种中所见的自然变异。在飞行过程中，加速度、速度和机动性的直接测量将使用计算机集成的高速摄像机进行。此外，还将测量载重能力和飞行过程中使用的能量。其次，在温室围护环境中进行一系列捕食回避实验，直接测量飞行性能受损的适应度后果。第三，对菊科中许多物种的形态和飞行表现的相关进化模式的测量将揭示性选择的进化结果。如果眼柄损害运动能力，机体设计的代偿性变化预计会在家族中进化，以减少运动成本。这种补偿性变化将间接表明，这种业绩的减少是有选择性地重要的。这个研究项目结合了多个学科，肯定会对运动成本和第二性装饰进化之间的相互作用产生新的见解。PI的教育活动将主要集中在来自印第安人保留地学校和农村学校的弱势大学预科学生。这两个群体，尤其是印第安人，传统上在大学和科学领域的代表性都不足。南达科他州有大量的印第安人（约10%）和大量的农村人口。通过与流动科学实验室（MSL）的讲师合作，PI将为MSL撰写一篇题为“性选择和昆虫多样性：第二性装饰”的论文。为MSL开发的外展项目将使美国原住民保留地和农村学校的K-12学生了解科学和发现的过程。这项外展计划有可能对整个南达科他州成千上万的人产生积极影响。

CAREER: PERFORMANCE AND FITNESS CONSEQUENCES OF INSECT ORNAMENTSJOHN G. SWALLOWUNIVERSITY OF SOUTH DAKOTASexual selection is responsible for much of the morphological diversity among animals and is often expressed in the form of male ornamental displays. Sexual selection theory indicates that these display traits do not come without costs, such that the displays and their costs are countered by natural selection. Stalk-eyed flies provide the ideal model system to test for costs and tradeoffs related to male ornamentation. All species in this extraordinary family display exaggerated head morphology, with eyes and antennae displaced at the end of long stalks, and interspecific variation in eye span can be more than ten-fold. Furthermore, all available evidence indicates that eye stalks are critical sexual signals used in both male-male competition and female choice. This study will examine the effects of elongated eye stalks on flight performance and survivorship of stalk-eyed flies to assess whether these effects run counter to the effects of sexual selection. To achieve this goal, the PI will integrate information from three distinct avenues of research. First, to establish a link between morphology and performance, variation in eye span and locomotor performance will be measured in a single species, Cyrtodiopsis dalmanni, to test for trade-offs between secondary sexual traits and adaptations for flight. For this study, lines of C. dalmanni that have been bidirectionally selected for increased and decreased eye span will be used to increase the natural variation seen in this species. Direct measurements of acceleration, speed and maneuverability during flight will be made using computer-integrated high speed video cameras. Additionally, load lifting capacity and energy used during flight will be measured. Second, the fitness consequences of impaired flight performance will be directly measured in a series of predation avoidance experiments in greenhouse enclosures. Third, patterns of correlated evolution between morphology and flight performance measured on many species within the family Diopsidae will reveal evolutionary consequences of sexual selection. If eye stalks impair locomotor ability, compensatory changes in body design are predicted to evolve within the family to reduce the locomotor cost. Such compensatory changes would indirectly suggest that such reduction in performance was selectively important. This research program incorporates multiple disciplines and will certainly result in new insights regarding interactions between the costs of locomotion and the evolution of secondary sexual ornaments. The PI's educational activities will focus primarily on disadvantaged pre-college students from Native American reservation schools and rural schools. Both of these groups, particularly Native Americans, are traditionally underrepresented in both college and the sciences. South Dakota has both a large Native American population (~ 10%) and a large rural population. Through cooperation with the instructors affiliated with the Mobile Science Laboratory (MSL), the PI will develop a contribution on "Sexual selection and insect diversity: secondary sexual ornaments" for the MSL. Outreach projects developed for the MSL will expose K-12 students from Native American reservation and rural schools to the process of science and discovery. This outreach program has the potential to positively influence thousands of people throughout the state of South Dakota.