Doctoral Dissertation Research: Ecomorphological Implications of Primate Dietary Variability: An Experimental Model

本研究在一种成熟的实验物种（大鼠）中建立了灵长类动物颅骨生长模型，该模型模拟了环境资源的时间波动。新的综合分析包括影像学、形态学指标、组织学和血清学，对与出生后饮食特性和摄食行为变化相关的骨骼形态学和生理学进行了分类。本研究的多学科性质为发展研究与医疗机构之间的合作以及促进学生培训提供了许多独特的机会。结果将在科学和公共论坛上传播，并将对人类颅面健康产生更广泛的影响，因为它与饮食和影响口腔功能的许多疾病有关。人类头骨的进化和功能与食物所施加的机械需求密切相关。在灵长类动物和人类的进化过程中，这些饮食资源通常是季节性的，导致人们周期性地食用难以加工的“备用食物”。在对人类祖先化石和近亲（如傍人）的生态学解释中，经常援引这种饮食季节性。然而，尽管灵长类动物的饮食具有时空复杂性，但关于饮食特性的季节性对颅面发育的影响的研究却很少。这极大地阻碍了我们对灵长类动物生态学和进化的理解，以及摄食行为对骨骼生物学和人类颅面健康的影响。为了解决这一重大差距，本研究使用大鼠来测试随时间变化的饮食资源如何受到面部潜在骨骼发育中后备食物的影响。这项研究将使用各种成像技术来检查那些喂食备用食物的动物和那些没有喂食备用食物的动物之间的差异。这些现代方法弥补了灵长类动物骨骼生长的实验室和实地分析之间的差距。纵向方法将阐明行为变化对整个生长时期颅面形态和生理的影响，从而在多个生物体水平上深入了解颅骨发育。更全面地了解环境影响生物形态的方式，将有助于阐明骨骼生物学和饮食变化之间的关系，

This research develops a model of primate skull growth in a well-established experimental species (rats) that mimics temporal fluctuations in environmental resources. Novel integrative analyses involving imaging, morphological metrics, histology, and serology typify the skeletal morphology and physiology associated with postnatal variation in dietary properties and feeding behavior. The multidisciplinary nature of this study provides a number of unique opportunities to develop collaborations between research and medical facilities, and to promote student training. Results will be disseminated at scientific and public forums, and will have broader implications for human craniofacial health as it relates to diet and numerous disorders affecting oral utility.The evolution and function of the human skull is intimately related to the mechanical demands imposed by food items. Throughout primate and human evolution, these dietary resources have often been seasonal, resulting in the cyclical consumption of difficult-to-process "fallback foods." This dietary seasonality has often been invoked in ecological interpretations of fossil human ancestors and relatives, such as Paranthropus. However, despite the temporal and spatial complexity of primate diets, there is little work related to the impact of seasonality in dietary properties on craniofacial development. This greatly hinders our understanding of primate ecology and evolution as well as the influence of feeding behaviors for bone biology and human craniofacial health. To address this significant gap, this research uses rats to test how changing dietary resources across time are affected by fallback foods in underlying skeletal development of the face. The research will use a variety of imaging techniques to examine differences between those animals that are fed fallback foods and those that are not. Such modern methods bridge the gap between laboratory- and field-based analyses of skeletal growth in primates. A longitudinal approach will elucidate the effect of behavioral variation on craniofacial morphology and physiology across the entire growth period, providing insight into skull development at multiple organismal levels. A more complete understanding of the way environment impacts organismal form will shed light on the association between skeletal biology and dietary variability,