Doctoral Dissertation Research: Relationships between diet and tooth wear in primate evolution

牙齿是化石记录中最丰富的遗迹之一。它们提供了有关饮食和环境、行为和进化关系的信息。这个博士论文研究项目使用新的和新兴的技术来更好地理解牙齿形状、功能和饮食之间的关系，因为牙齿在灵长类动物成熟过程中发生了变化。由于许多分析方法需要磨损很小的牙齿，许多化石牙齿由于磨损程度而被排除在研究之外。该项目利用了牙齿磨损的各个阶段的数据，并描述了化石记录中单个灵长类物种的饮食特征，为早期猿类群落的研究提供了一个更全面的生态背景、多样性和适应意义的框架。此外，该项目为来自STEM中代表性不足的群体的本科生提供了研究机会。调查员还通过当地的自然历史博物馆和一个非营利性的科学和社会研究项目主持社区外展和参与活动。本项目旨在通过将最新的全冠牙齿地形分析方法与尖端的表面形状分割相结合，建立一种表征和区分不同饮食行为灵长类动物（宏观）牙齿磨损的新方法，提高早中新世灵长类动物饮食行为的分辨率。重要的是，整个磨损阶段的标本被用来重建饮食行为和变化。这项研究的动机是三个具体的问题：1)在现存的灵长类动物中，牙冠磨损的差异与不同的饮食有什么关系？2)个体尖端的磨损是否反映了现存灵长类动物对饮食分化的不同程度的分辨力？3)中新世早期卡他龙的磨损模式表明它们的饮食宽度如何？为了解决这些问题，使用牙科地形分析的变量：ariaDNE， 3D-OPCR和RFI来表征现存和化石标本的样本。表面分割技术的进步使这些聚集变量不仅可以在整个冠上有效地评估，而且可以在单个尖上有效地评估。这种新颖的方法及其在牙齿磨损阶段的应用可以大大提高牙齿功能随时间和冠表面变化的分辨率。此外，牙尖的个体化可以提供关于饮食信号在牙冠表面分布的重要见解，对评估古人类、其他灵长类动物和其他哺乳动物的牙齿功能和进化具有重要意义。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Teeth are among the most plentiful remains in the fossil record. They provide information about diet and environment, behavior, and evolutionary relationships. This Doctoral Dissertation Research project uses new and emerging techniques to better understand the relationships among tooth shape, function, and diet as teeth change across the course of primate maturation. Because many analytical methods require teeth with little wear, many fossil teeth are excluded from study due to levels of wear. This project leverages data across all stages of tooth wear and characterizes the diets of individual primate species represented in the fossil record, providing a more comprehensive framework of ecological context, diversity, and adaptive significance to be built for the study of early ape communities. In addition, this project provides research opportunities for undergraduates from groups underrepresented in STEM. The investigator also hosts community outreach and engagement events through the local natural history museum and a nonprofit science and social studies program.This project aims to improve resolution of Early Miocene primate dietary behaviors by combining updated methods of whole-crown dental topographic analysis with cutting-edge surface shape segmentation into a new approach for characterizing and differentiating (macroscopic) tooth wear among primates with different dietary behaviors. Importantly, specimens across the spectrum of wear stages are used to inform reconstructions of dietary behaviors and variation. The research is motivated by three specific questions: 1) How do differences in tooth crown wear correlate with different diets in extant primates? 2) Does wear on individual cusps reflect different degrees of resolution for dietary differentiation in extant primates? and 3) What do patterns of wear in Early Miocene catarrhines indicate regarding their dietary breadth? To address these questions, a sample of extant and fossil specimens are characterized using variables from dental topographic analysis: ariaDNE, 3D-OPCR, and RFI. Advances in surface segmentation techniques enable these aggregate variables to be efficiently assessed not only on whole crowns, as is typical, but also on individual cusps. This novel approach and its application across stages of tooth wear can greatly improve resolution of how tooth function varies over time and across the crown surface. Moreover, the individuation of cusps can provide important insights regarding the distribution of dietary signal across the tooth crown surface, with implications for assessing dental function and evolution in hominins, other primates, and other mammals.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.