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

在15至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离家数千英里的地方，在奴役中经历了有限的社会生活和流动性。这个博士论文项目研究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如何随着时间的推移而形成和变化，探索基因流和其他进化过程，可以解释生物变异是如何分布的，并调查可能没有反映在历史移民数据中的生物相关性模式。该项目支持来自科学代表性不足的群体的学生的博士培训，多点研究合作，与社区成员的外联以及学生辅导。该项目还与佛罗里达大学的大学拓展计划合作开发课程和研讨会，以提高来自STEM研究中历史上代表性不足的群体的学生的中学后入学率和完成率。该项目的理论框架植根于随机微进化预期和散居研究。微进化过程，如人口分层推断的前提下，基因流，而不是自然选择，是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，欧洲国家直接影响了跨越大西洋形成的散居人口的基因流动。该项目提出了两个核心问题：（1）哪些非洲人和非洲后裔散居群体显示出根据颅骨形态估计的高度生物相关性，以及这些数据如何确定历史移民数据没有描述的基因流动证据？（2）鉴于社会和法律的限制造成了被奴役者之间的实际隔离，散居群体是否比非洲群体显示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测量方法从成人颅骨遗骸中收集3D标志，并使用这些数据来统计分析颅骨形态的组内和组间变化。将从21个地点收集数据，包括805名成年非洲后裔的头骨遗骸。该奖项反映了NSF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。

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.