Variation in human skeletal phenotype across a subsistence strategy transition
Open Access
- Author:
- De Mars, Lily
- Graduate Program:
- Anthropology (PHD)
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- August 20, 2021
- Committee Members:
- Nina Jablonski, Major Field Member
Jonas Rubenson, Outside Unit & Field Member
Tim Ryan, Chair & Dissertation Advisor
Douglas Bird, Major Field Member
George Milner, Major Field Member
Mary Katherine Shenk, Professor in Charge/Director of Graduate Studies - Keywords:
- Trabecular bone
cortical bone
human variation
microCT
biological anthropology
bone phenotype
subsistence strategy - Abstract:
- Present-day modern humans have relatively gracile, or lightly built, skeletons compared to fossil hominins and non-human primates. Previous research has suggested that modern human skeletal gracility coincides with the adoption of agricultural subsistence strategies and the changes in mobility and activity patterns that were likely associated. Most research on modern human bone structural variation has focused on comparing bone structure among geographically, genetically, and behaviorally distinct human groups within the context of changes in subsistence and activity patterns. However, this approach does not consider other factors known to influence bone structure, including population history and environmental context. In the following chapters, high-resolution microcomputed tomography (µCT) image data of the tibial diaphysis, distal tibia, talus, and calcaneus are used to quantify bone structure variables in order to investigate variation in cortical bone cross-sectional geometry and trabecular bone microarchitecture. The skeletal remains included in this dissertation are from three human groups, which, based on archaeological evidence were environmentally and likely genetically similar, but behaviorally distinct. The resulting data is used to assess the influence of activity and mobility patterns on variation in modern human skeletal phenotype. Integrating archaeological evidence of human behavior, 3DµCT imaging and visualization, and quantification of bone structure to investigate the relationship between activity and human skeletal phenotype allows for better control of factors besides activity that are known to influence bone structure, such as environment and genetic ancestry, relative to previous studies. The results provide insight into the effects of variation in subsistence strategy, mobility, and physical activity on human skeletal morphology and help strengthen interpretations of human (and fossil hominin) behavior in the past. Additionally, by including both cortical and trabecular tissue levels, this research addresses more fundamentally biological questions regarding the responsiveness of each skeletal tissue level to shifts in subsistence strategy.