No abstract

Ungulate gnawing on bone has been reported in the taphonomic and zooarchaeological literature, but there are no known reports of ungulates altering human remains. Herein, we report on the first known photographic evidence of deer gnawing human remains. As described in nonhuman scavenging literature, forking of the bone characterizes the taphonomic effect of deer gnawing in this case, which is distinct from the effect caused by other scavengers. This type of osteophagia during the winter season is consistent with previously documented behavior of deer gnawing on nonhuman bone, possibly to obtain minerals absent in their diet. In this study, we briefly discuss the distinguishing features of ungulate gnawing, the reasons for this behavior, and possible confusion with other common types of scavenging and modification. This report contributes to taphonomic literature covering the range of animal interactions with human skeletal remains.

: We investigate whether femur morphology is affected by body mass (BM). To establish deformations associated with obesity, we propose an atlas estimation framework based on diffeomorphic shape mapping that relaxes the point correspondence requirement common to many conventional shape modeling approaches. : The study sample consisted of femora from 18 normal weight (BMI between 20-25) and 18 obese (BMI > 30) individuals (Texas State University Donated Skeletal Collection). Bone surface models (2,500 vertices and approximately 5,000 faces) were generated from CT scans of the specimens (512x512 matrix, 0.625x0.625x0.5 mm voxels). The surface models were input to an optimization algorithm that yielded an atlas representation of shape variability consisting of a mean bone template and diffeomorphic deformations matching the template onto each specimen. The accuracy of normal weight vs. obese classification using principal atlas deformation modes was established in leave-one-out experiments with Support Vector Machine (SVM) classifier. : We achieved 75% classification accuracy in leave-one-out SVM experiments, indicating the possibility of functional skeletal adaptations to increased body mass. By visualizing the bone surface deformation given by the SVM classification direction, we found that morphological alterations associated with obesity might include relative thickening of the femoral neck and the trochanters, and retroversion of the femoral head. : The landmark-free atlas estimation algorithm enabled detection of morphological femur variants that might be predictive of elevated body mass.

Whole-body donations (n = 6) were placed in various experimental fire-death scenarios to understand the histological effects of thermal alteration on bones and teeth. Midshaft samples of the femur, 6th rib, and metatarsal were removed from each donor pre- and post-burning to examine histomorphometric differences and test established age-at-death estimation methods. Dental samples were taken post-burning to test the applicability of dental cementum analysis for age-at-death estimation. Significant differences in osteon area or Haversian canal area between some pre- and post-burn samples were found although no patterns related to temperature or element were observable. The femoral age estimates across pre- and post-burn samples were 91% accurate across all donors. The point age estimates from the ribs compared to known age were significantly different (t(10) = 6.88, p < 0.001) with an average difference of −18.53 years. Dental age estimates of post-burn samples were not significantly different from the known donor age (t(3) = −0.74, p = 0.512) with an average difference of −3.96 years. Overall, the results of this study show that thermally altered remains can be used for histologic age-at-death analysis of cortical bone and dental cementum, within certain burning parameters.