Doctoral Dissertation Improvement: Craniodental Form, Functional Convergence, and the Evolution of Dietary Preferences

博士论文改进：颅齿形态、功能趋同和饮食偏好的演变

• 批准号: 0127915
• 负责人: Matthew Ravosa
• 金额: $ 0.7万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-11-01 至 2002-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0127915&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Improvement; Craniodental; Form

Researchers have long sought to understand the environmental variables underlying behavioral and anatomical evolution in early primates. While disagreement persists over which factors were of greatest significance, diet is widely thought to have played an important role. Therefore, efforts to illuminate trends in early primate evolution will require the ability to reconstruct diet from fossils. To this end, investigators over the past two decades have attempted to identify features of the skull and dentition that can be used to achieve this. While these studies have identified many such features, significant gaps remain. First, to ensure that a structure and function are consistently linked in a specified manner, they must be evaluated in ecologically similar, yet distantly related groups. As few predictions have been tested in nonprimates, it is unclear whether patterns observed in these animals can confidently be extrapolated to their distant fossil relatives. Second, the study of jaw or dental form alone is not sufficient to discriminate among all diets. Since previous studies have considered these separately, the usefulness of evaluating both to fully characterize a species feeding habits remains largely unexplored. The goal of this research is to fill these gaps by using marsupials as a natural experiment to test the hypotheses that dental and mandibular form reflect a species' diet. Specifically, ten predictions relating tooth surface features and the internal and external proportions of the lower jaw (determined from x-ray film) to the physical properties of a species' diet will be evaluated. By testing these predictions in a group that extensively overlaps primates in most aspects of feeding ecology, this study will not only allow greater confidence in the utility of these variables for inferring diet in extinct primates, but it will also greatly expand our understanding of the ecological bases of evolution in mammals in general.

研究人员长期以来一直试图了解早期灵长类动物行为和解剖进化背后的环境变量。 虽然对于哪些因素最重要仍存在分歧，但人们普遍认为饮食发挥了重要作用。 因此，阐明早期灵长类动物进化趋势的努力需要能够从化石中重建饮食。 为此，研究人员在过去二十年中一直试图确定可用于实现这一目标的头骨和牙列的特征。 尽管这些研究已经确定了许多此类特征，但仍然存在重大差距。 首先，为了确保结构和功能以特定的方式一致地联系在一起，必须在生态上相似但相关性较远的群体中对它们进行评估。 由于在非灵长类动物中测试的预测很少，目前尚不清楚在这些动物中观察到的模式是否可以自信地推断出它们的远亲化石。 其次，仅对颌骨或牙齿形状的研究不足以区分所有饮食。 由于之前的研究分别考虑了这些因素，因此评估两者以充分表征物种摄食习性的有用性在很大程度上仍未得到探索。 这项研究的目的是通过使用有袋动物作为自然实验来测试牙齿和下颌形状反映物种饮食的假设，从而填补这些空白。 具体来说，将评估与牙齿表面特征和下颌的内部和外部比例（通过 X 射线胶片确定）与物种饮食的物理特性相关的 10 个预测。 通过在一个在摄食生态学的大多数方面与灵长类动物广泛重叠的群体中测试这些预测，这项研究不仅可以让人们对这些变量在推断灭绝灵长类动物饮食方面的效用更有信心，而且还可以极大地扩展我们对哺乳动物进化的生态基础的理解。