Anthropology, Humboldt State University
Saturday All day, Clinch Concourse
The mandibular torus, variably present in humans, is thought to be a threshold trait caused by variation in the LPR5 gene associated with bone density; however, those with the trait may only develop one or more tori after a threshold of masticatory stress has been reached. Whereas some mutations in this gene are known to cause an increased or decreased gonial angle, there is little to no information about the relationship between the gonial angle and mandibular torus. Findings on the rate of mandibular torus occurrence in similar populations are somewhat inconsistent. For instance, different studies of present-day Thai populations have reported rates of mandibular torus at 9.2% and 29.9%. Such results have led to significant skepticism as to the reliability of the trait in biodistance analysis and whether mandibular torus presence can indicate anything about a population’s lifestyle. We examined the relationship between the mandibular torus and gonial angle in modern skeletal collections in the United States, also recording variables such as: wear on the temporomandibular joint, attrition, approximate age of the individual, edentulism and other exostoses. Angle measurements in this study were taken using a goniometer. Although preliminary, our results support that factors other than heredity may reliably correlate with the mandibular torus. If establishing other correlates can increase the reliability with which this trait can be predicted, it could provide sound behavioral and biological insight.