Doctoral Dissertation Research: Influence of environment and population structure on human skeletal variation

University Of Missouri-Columbia, Columbia MO

Investigators

Abstract

Humans vary in body size and proportions, and the underlying drivers of this variation are not fully understood. Differences in body form can be adaptive for certain environments, such as assisting in thermoregulation of the body through the dissipation or retention of heat, but can also be related to factors such as genetic drift and population history. This doctoral dissertation research will examine human skeletal variation to understand the impact of various environmental factors on human body form across a wide geographical range. The project will help to elucidate how environmental factors may have complex, differential effects in males versus females and across different parts of the skeleton. Skeletal data from the project will be compiled into a freely accessible online database. The addition of data for groups and regions of the world that are currently underrepresented in biological and forensic studies will increase understanding of human variation and global diversity. The project will also foster international research collaborations and student training at the undergraduate and graduate levels. Asia has diverse climates, high population densities, and a long history of human habitation. Using a multidisciplinary methodological approach, this study of Asian populations will meaningfully quantify proportional differences resulting from environmental variables in a way not possible with previous ecogeographic methods. Standard skeletal measurements and landmarks will be collected to allow for comparisons across geographic regions as well as further examination of variation in the size and shape of the face, cranial vault, and birth canal between the sexes and populations. The analyses will account for the potential influence of nonadaptive forces such as drift and migration on body form by pairing skeletal measurements with appropriately matched genetic data and local weather station information for statistical analysis. Linear mixed effects models testing for evidence of adaptation due to environmental factors will contain both head and body data of male and female individuals from each population. Differences in the size and shape of the pelvis between the sexes along with population differences in pelvic morphology will be evaluated using Procrustes fit and principal components analyses as well as size and shape dimorphism indices. 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.