Abstract
In this study we present data on bone mineral density (BMD) values for the cranial and post-cranial skeleton of the leopard tortoise (Stigmochelys pardalis). We found significant inter and intra-skeletal variation in different values of BMD within this species. The intra-skeletal, but not inter-skeletal pattern, was comparable to that of terrestrial mammals of similar size, despite differences in bone structure. Overall, the tortoise has bone density that is intermediate between that of leporids (rabbits/hares) on the one hand and canids (dogs/wolves etc.) and marmots on the other. In this study we have used random effects to test regression models of BMD and demonstrate their value over the simple linear regression models that are currently in use. Finally, we applied the modern leopard tortoise proxy data to test whether different parameters of BMD impact survivorship of tortoise bones in the Holocene strata from Wonderwerk Cave (Northern Cape Province, South Africa). Results indicate that this assemblage has undergone some degree of bone density-mediated attrition, probably influenced by burning and deposition time rather than animal agents.
| Original language | English |
|---|---|
| Pages (from-to) | 64-78 |
| Number of pages | 15 |
| Journal | Quaternary International |
| Volume | 495 |
| DOIs | |
| State | Published - 30 Nov 2018 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2018 Elsevier Ltd and INQUA
Funding
We dedicate this paper to James Brink on the occasion of his 60th birthday. James has played a positive role for us, as a valued colleague and research collaborator and we offer him our warm wishes for the coming years. We would like to acknowledge the Palaeontological Scientific Trust (PAST) for their financial support towards SH's PhD research and to thank the Centre of Excellence for Nutrition at the North West University for permission to undertake the bone density scans and Magda Uys who did the scanning. Special thanks to Beryl Wilson of the McGregor Museum, Kimberley who helped to collect the dead tortoises that are now curated in the National Museums collection including the specimen used in this article and to Linda Wheeler who made the sketches of the tortoise bones. We thank the two anonymous reviewers for their useful comments which helped to improve this paper. We dedicate this paper to James Brink on the occasion of his 60 th birthday. James has played a positive role for us, as a valued colleague and research collaborator and we offer him our warm wishes for the coming years. We would like to acknowledge the Palaeontological Scientific Trust (PAST) for their financial support towards SH's PhD research and to thank the Centre of Excellence for Nutrition at the North West University for permission to undertake the bone density scans and Magda Uys who did the scanning. Special thanks to Beryl Wilson of the McGregor Museum, Kimberley who helped to collect the dead tortoises that are now curated in the National Museums collection including the specimen used in this article and to Linda Wheeler who made the sketches of the tortoise bones. We thank the two anonymous reviewers for their useful comments which helped to improve this paper.
| Funders | Funder number |
|---|---|
| Centre of Excellence for Nutrition | |
| North West University | |
| Palaeontological Scientific Trust | |
| PAST |
Keywords
- Computed tomography
- Leopard tortoise
- Photon absorptiometry
- Reptiles
- Taphonomy
- Wonderwerk cave