DISSERTATION RESEARCH: Form, function, and modularity in the modern bat skull: understanding the evolution of phenotypic complexity

蝙蝠是现代哺乳动物中物种最丰富的群体之一，尤其以其生态多样性而闻名。蝙蝠在世界范围内占据着许多生态位，发挥着各种生态系统功能和服务。进化生物学家经常结合形态学研究生态多样性，因为物理特征与性能和功能密切相关。蝙蝠的头骨有一个高度复杂的形状，可以编码有关生态相互作用的信息。多重选择压力影响了现代蝙蝠头骨的复杂形态，通过研究其形态进化，本研究将揭示这些进化过程的生态背景。这项研究将综合博物馆藏品与尖端成像技术和形状分析，以模拟高度复杂的生物结构的进化。研究结果将被整合到与教育非营利组织和自然历史博物馆合作的推广项目中。形态多样性和生态多样性都是生物多样性的重要组成部分，通过在公共教育中强调这两个方面，研究人员将强调生态和进化背景在理解生态系统功能和服务方面的重要性。为了实现这些目标，研究人员将对各种现代蝙蝠头骨进行高分辨率的x射线计算机微断层扫描（microCT）。MicroCT扫描捕捉到了传统的、简单的测量方法无法捕捉到的生物结构的复杂性。这些数据可用于性状进化和物理繁殖的多维分析。扫描后，蝙蝠头骨将被数字化，以使用基于地标的几何形态计量学（一种量化形状变化的方法）进行分析。然后，研究人员将量化现代蝙蝠头骨中存在的形态多样性的数量，并将在蝙蝠系统发育树上模拟形状进化的速度。头骨的模块可能会针对进食、回声定位和听力等不同功能进行优化，这些模块将被独立分析，以验证不同生态压力相互作用来控制头骨形状进化的假设。最终，这些数据将用于测试现代蝙蝠的形态多样性、生态功能和进化多样性之间的联系。

Bats are one of the most species-rich groups of modern mammals, and are particularly known for their ecological diversity. Bats fill numerous ecological niches worldwide, performing a variety of ecosystem functions and services. Evolutionary biologists often study ecological diversity in conjunction with morphology, as physical traits can be closely tied to performance and function. The bat skull has a highly complex shape that encodes information about ecological interactions. Multiple selective pressures influence the complex form of a modern bat skull, and by studying its morphological evolution, this research will reveal the ecological context of those evolutionary processes. This research will synthesize museum collections with cutting-edge imaging technology and shape analyses to model the evolution of a highly complex biological structure. The findings will be integrated into outreach programs in partnership with educational nonprofits and natural history museums. Both morphological and ecological diversity are critical components of biodiversity, and by emphasizing both facets in public education, the researchers will stress the importance of both ecological and evolutionary context in understanding ecosystem functions and services.To accomplish these goals, the researchers will produce high-resolution X-ray computed microtomography (microCT) scans of a wide range of modern bat skulls. MicroCT scanning capture much of the complexity of biological structures that is lost with traditional, simple measurements. The data can be used for multidimensional analyses of trait evolution and physical reproductions. After scanning, bat skulls will be digitized for analysis using landmark-based geometric morphometrics, a method for quantifying shape variation. The researchers will then quantify the amount of morphological diversity present among modern bat skulls, and will model rates of shape evolution across the bat phylogenetic tree. Modules of the skull, which may be optimized for different functions like feeding, echolocation, and hearing, will be analyzed independently, to test the hypothesis that different ecological pressures interact with each other to govern skull shape evolution. Ultimately, these data will be used to test the links among morphological diversity, ecological function, and evolutionary diversification across modern bats.