Abstract
In order to discuss dietary change over time by the use of stable isotopes, it is necessary to sort out the underlying processes in isotopic variation. Together with the dietary signal other processes have been investigated, namely metabolic processes, collagen turnover and physical growth. However, growth and collagen turnover time have so far been neglected in dietary reconstruction based on stable isotopes. An earlier study suggested that cave bears (Ursus spelaeus) probably gave birth to cubs during dormancy. We provide an estimate of the effect on stable isotopes of growth and metabolism and discuss collagen turnover in a population of cave bears. Based on a quantitative model, we hypothesized that bear cubs lactated their mothers during their first and second winters, but were fed solid food together with lactation during their first summer. This demonstrates the need to include physical growth, metabolism and collagen turnover in dietary reconstruction. Whereas the effects of diet and metabolism are due to fractionation, growth and collagen turnover are dilution processes.
Full Text
The Full Text of this article is available as a PDF (123.6 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Akesson K., Vergnaud P., Gineyts E., Delmas P. D., Obrant K. J. Impairment of bone turnover in elderly women with hip fracture. Calcif Tissue Int. 1993 Sep;53(3):162–169. doi: 10.1007/BF01321832. [DOI] [PubMed] [Google Scholar]
- Ebeling P. R., Atley L. M., Guthrie J. R., Burger H. G., Dennerstein L., Hopper J. L., Wark J. D. Bone turnover markers and bone density across the menopausal transition. J Clin Endocrinol Metab. 1996 Sep;81(9):3366–3371. doi: 10.1210/jcem.81.9.8784098. [DOI] [PubMed] [Google Scholar]
- Garnero P., Sornay-Rendu E., Chapuy M. C., Delmas P. D. Increased bone turnover in late postmenopausal women is a major determinant of osteoporosis. J Bone Miner Res. 1996 Mar;11(3):337–349. doi: 10.1002/jbmr.5650110307. [DOI] [PubMed] [Google Scholar]
- Harkness D. D. Further investigations of the transfer of bomb 14 C to man. Nature. 1972 Dec 1;240(5379):302–303. doi: 10.1038/240302a0. [DOI] [PubMed] [Google Scholar]
- LIBBY W. F., BERGER R., MEAD J. F., ALEXANDER G. V., ROSS J. F. REPLACEMENT RATES FOR HUMAN TISSUE FROM ATMOSPHERIC RADIOCARBON. Science. 1964 Nov 27;146(3648):1170–1172. doi: 10.1126/science.146.3648.1170. [DOI] [PubMed] [Google Scholar]
- Langeland N. The influence of oestrogen on bone metabolism. Arch Orthop Trauma Surg. 1978 Aug 30;92(2-3):149–152. doi: 10.1007/BF00397951. [DOI] [PubMed] [Google Scholar]
- Nelson R. A. Protein and fat metabolism in hibernating bears. Fed Proc. 1980 Oct;39(12):2955–2958. [PubMed] [Google Scholar]
- Okazaki R., Totsuka Y., Hamano K., Ajima M., Miura M., Hirota Y., Hata K., Fukumoto S., Matsumoto T. Metabolic improvement of poorly controlled noninsulin-dependent diabetes mellitus decreases bone turnover. J Clin Endocrinol Metab. 1997 Sep;82(9):2915–2920. doi: 10.1210/jcem.82.9.4258. [DOI] [PubMed] [Google Scholar]
- Ravn P., Fledelius C., Rosenquist C., Overgaard K., Christiansen C. High bone turnover is associated with low bone mass in both pre- and postmenopausal women. Bone. 1996 Sep;19(3):291–298. doi: 10.1016/8756-3282(96)00201-3. [DOI] [PubMed] [Google Scholar]
- Sone T., Miyake M., Takeda N., Fukunaga M. Urinary excretion of type I collagen crosslinked N-telopeptides in healthy Japanese adults: age- and sex-related changes and reference limits. Bone. 1995 Oct;17(4):335–339. doi: 10.1016/s8756-3282(95)00243-x. [DOI] [PubMed] [Google Scholar]
- Sorva R., Anttila R., Siimes M. A., Sorva A., Tähtelä R., Turpeinen M. Serum markers of collagen metabolism and serum osteocalcin in relation to pubertal development in 57 boys at 14 years of age. Pediatr Res. 1997 Oct;42(4):528–532. doi: 10.1203/00006450-199710000-00018. [DOI] [PubMed] [Google Scholar]
- Thorsen K., Kristoffersson A., Hultdin J., Lorentzon R. Effects of moderate endurance exercise on calcium, parathyroid hormone, and markers of bone metabolism in young women. Calcif Tissue Int. 1997 Jan;60(1):16–20. doi: 10.1007/s002239900179. [DOI] [PubMed] [Google Scholar]
- White C. D., Armelagos G. J. Osteopenia and stable isotope ratios in bone collagen of Nubian female mummies. Am J Phys Anthropol. 1997 Jun;103(2):185–199. doi: 10.1002/1096-8644(199706)103:2<185::AID-AJPA11>3.0.CO;2-#. [DOI] [PubMed] [Google Scholar]