Doctoral Dissertation Research: The Evolutionary Significance of Skeletal Variation in Homo naledi

最近人类物种“纳勒迪人”的发现给人类进化带来了新的复杂性和新的问题。在这个博士论文项目中，研究者将使用3D扫描技术来量化许多纳勒迪人的骨骼变异，并将结果置于更广泛的灵长类动物比较背景下。除了提供纳勒迪人变异的进化背景外，该项目还将在多个尺度上强调遗传和骨骼变异之间的关系，这可能用于在生物考古、法医和古人类学组合中识别相关个体。这项研究将生成数百种灵长类动物的3D模型，这些模型将向公众开放，创建新的教育材料，可以3D打印并用于课程计划和推广。此外，通过与本地和国际大学的密切合作，对3D成像感兴趣的本科生将继续使用这些扫描进行独立的研究项目。目前尚不清楚最近发现的纳勒迪人个体是一个小的、孤立的种群的一部分，还是一个更大的、地理上多样化的物种，可能与现代人类有过互动。在这个项目中，纳勒迪人个体之间的差异将使用五个颅后元素的三维几何形态计量学评估进行量化。包含已知和未知生物关系的个体的比较现代人类和黑猩猩样本将被用作在多个尺度上探索变异的基线。为此，本项目有三个目标：1)检验现代人类和黑猩猩种群水平上和种群水平下遗传和形态距离之间存在正相关关系的假设；2)量化naledi人内部的变异，并将其与现代人类和黑猩猩的变异进行比较；3)通过确定H. naledi与生物亲属的相似程度来确定这种变异的背景。将评估有关种群隔离和相对大小的许多进化情景，以确定哪种情景最有可能产生在纳勒迪人身上看到的变异。这样做，这个项目将阐明纳勒迪人的进化史，以及纳勒迪人与现代人类之间相互作用的可能性。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。

The recent discovery of the hominin species Homo naledi has introduced new complexity and new questions about human evolution. In this doctoral dissertation project, the investigator will use 3D scanning technology to quantify skeletal variation across a number of H. naledi individuals and situate the results in a broader comparative primate context. Beyond providing an evolutionary context for the variation in H. naledi, this project will highlight the relationship between genetic and skeletal variation at multiple scales, which may be used to identify related individuals within bioarchaeological, forensic, and paleoanthropological assemblages. The research will generate hundreds of 3D models of three primate species, which will be made available to the public, creating new educational materials that can be 3D printed and used for lesson plans and outreach. Additionally, through close collaborations with local and international universities, undergraduates with interests in 3D imaging will continue to engage in independent research projects using these scans.It is not known whether the recently discovered H. naledi individuals represent part of a small, isolated population or a larger, geographically diverse species that may have interacted with modern humans. In this project, the variation between H. naledi individuals will be quantified using 3D geometric morphometric assessment of five postcranial elements. Comparative modern human and chimpanzee samples containing individuals of known and unknown biological relationships will be used as baselines to explore variation at multiple scales. To this end, this project has three objectives: 1) to test the hypothesis that there is a positive relationship between genetic and morphological distance at and below the population level in modern humans and chimpanzees; 2) to quantify the variation within H. naledi and compare it to the variation calculated for modern humans and chimpanzees; and 3) to contextualize this variation by determining the extent to which H. naledi resembles biological relatives. A number of evolutionary scenarios concerning population isolation and relative size will be evaluated to determine which scenario most likely produced the variation seen in H. naledi. In so doing, this project will shed light on H. naledi’s evolutionary history and the possibility of interaction between H. naledi and modern humans.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.