Doctoral Dissertation Research: Morphological biodistances as indicators of slave trade migration histories in the African Diaspora

在15-19世纪，数百万人因奴隶贸易而流离失所。这些制度深刻地影响了人口动态，因为被奴役的人被运送到远离家园数千英里的地方，并在奴役中经历有限的社会生活和流动性。这篇博士论文研究了这些被奴役的人及其后代的骨骼形态，以了解某些生物群体是如何随着时间的推移而形成和变化的，探索了基因流动和其他可能解释生物变异如何分布的进化过程，并调查了历史迁徙数据中可能没有反映的生物关联模式。该项目支持对科学方面代表性不足的群体的学生进行博士培训、多点研究合作、与社区成员的接触以及学生指导。该项目还与佛罗里达大学的学院外展计划合作开发课程和研讨会，以增加STEM研究中历史上代表性不足的群体的中学后入学和完成学业。该项目的理论框架植根于随机微进化预期和散居研究。种群分层等微观进化过程是从这样一个前提推断出来的，即基因流动而不是自然选择是对观察到的生物模式的主要影响。此外，从该项目中收集的解释来自奴隶贸易历史，在那里，欧洲国家直接影响了大西洋彼岸形成的散居国外人口的基因流动。该项目提出了两个核心问题：(1)根据颅骨形态估计，哪些非洲人和非洲人后裔群体显示出高度的生物相关性，以及这些数据如何识别历史移民数据没有描述的基因流动的证据？以及，(2)鉴于社会和法律限制造成了被奴役人群之间的物理隔离，散居国外的群体是否比非洲群体表现出更强的人口分层和遗传隔离的证据？为了研究这些问题，本项目应用几何形态计量学方法从成人颅骨残骸中收集3D地标，并使用这些数据统计分析组内和组间颅骨形态的差异。数据将从21个地点收集，包括805个非洲成年后裔的头骨遗骸。这些样本代表了不同的地区。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Millions of people were displaced due to slave trade during the 15th – 19th centuries. These systems profoundly influenced population dynamics as enslaved people were transported thousands of miles from their homes and experienced restricted social life and mobility in enslavement. This doctoral dissertation project examines skeletal morphology of these enslaved people and their descendants to understand how certain biological groups formed and changed over time, explores gene flow and other evolutionary processes that may explain how the biological variation is distributed, and investigates patterns of biological relatedness that may not be reflected in historic migration data. The project supports the doctoral training of a student from an underrepresented group in science, a multi-point research collaboration, outreach with community members, and student mentoring. The project also develops curricula and seminars in collaboration with the University of Florida’s College Reach Out Program to increase postsecondary admission and completion for students from groups historically underrepresented in STEM research. This project’s theoretical framework is rooted in stochastic microevolutionary expectations and diaspora studies. Microevolutionary processes such as population stratification are inferred from the premise that gene flow, rather than natural selection, is the main influence on observed biological patterns. Further, interpretations gleaned from the project derive from slave trade history, where European nations directly influenced the gene flow of the diaspora populations that formed across the Atlantic. The project asks two central questions: (1) What African and Afro-descendant diaspora groups show high biological relatedness as estimated by cranial morphology, and how do these data identify evidence of gene flow not otherwise described by historical migration data? and, (2) Given the social and legal restrictions that created physical separation among enslaved persons, do diaspora groups show stronger evidence of population stratification and genetic isolation than African groups? To investigate these questions, this project applies geometric morphometric methods to collect 3D landmarks from adult human cranial remains and uses these data to statistically analyze within-group and between-group variation in cranial morphology. Data will be collected from twenty-one sites, comprising cranial remains of 805 adult African descendants. These samples represent a variety of regions.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.