Stable carbon isotope ratios diets

Lee-Thorp, J.A., Sealy, J.C. and van der Merwe, N.J. 1989 Stable carbon isotope ratio differences between bone collagen and bone apatite, and their relationship to diet. Journal of Archaeological Science 16 585-599. 

Chisholm, B.S., Nelson, D.E. and Schwarcz, H.P. 1982 Stable-carbon isotope ratios as a measure of marine versus terrestrial protein in ancient diets. Science 216 1131-1132. 

Stable Carbon Isotope Ratios as Indicators of Prebistoric Human Diet... 

Lee-Thorp JA, Sealy JC, van der Merwe NJ (1989) Stable carbon isotope ratio differences between bone collagen and bone apatite, and their relationship to diet. J Archaeol Sci 16 585-599 Lee-Thorp JA, van der Merwe NJ, Brain CK (1994) Diet of Australopithecus robustus at Swartkrans from stable carbon isotopic analysis. J Human Evol 27 361-372 Lindars ES, Grimes ST, Mattey DP, Collinson ME, Hooker JJ, Jones TP (2001) Phosphate 5 0 determination of modem rodent teeth by direct laser fluorination An appraisal of methodology and potential application to palaeoclimate reconstmction. Geochim Cosmochim Acta 65 2535-2548 Linder HP (1986) The evolutionary history of the Poales/Restionales—A hypothesis. Kew Bull 42 297-318... 

After chemical pretreatment, the samples are burnt to produce carbon dioxide and nitrogen. A small amount of this gas is bled into a mass spectrometer, where the stable isotope ratios of carbon and nitrogen are measured. These ratios provide useful information on the purity of the sample and clues about the diet and climatic conditions of the living organism. The carbon isotope ratio is also used to correct for isotopic fractionation in the radiocarbon measurement. The carbon dioxide is collected in a glass ampoule or converted to graphite for radiocarbon measurement on the AMS system. 

Stable carbon isotope analysis is particularly useful in New World dietary studies since maize is often the only C4 plant contributing significantly to human diets its contribution to bone collagen and to bone apatite may be estimated by interpolation. Some caution is warranted, however, if succulent plants were present, since they utilize the alternative CAM (crassulacean acid metabolism) photosynthetic pathway which results in carbon isotope ratios similar to those of C4 plants. Nevertheless, CAM plants are unlikely to have been major sources of dietary protein, whether consumed directly or indirectly through herbivorous faunal intermediaries. 

Keegan, W.F. and DeNiro, M.J. 1988 Stable carbon- and nitrogen- isotope ratios of bone collagen used to study coral-reef and terrestrial components of prehistoric Bahamian diet. American Antiquity 53 320-336. 

Also the stable isotopes of nitrogen, like those of carbon, are fractionated when nitrogen is incorporated into the plants. Determining the isotopic ratios between nitrogen-15 and nitrogen-14 in animal remains also reveals information on the diets of ancient animals and humans (White 1999 de Niro 1987). 

Sealy, J. (1997) Stable carbon and nitrogen isotope ratios and coastal diets in the Later Stone Age of South Africa a comparison and critical analysis of two data sets. Ancient Biomolecules 1, 131 147. 

Minor element contents and isotopic ratios are used for physiological purposes. Sr/Ca ratios in bone and teeth are said to reflect the diet of the animal (herbivores versus carnivores). Stable isotope analysis of teeth and bones provides direct information on the lifetime diets the nitrogen isotopes reflect the trophic level of the protein that has been consumed. Within an ecosystem, they can identify herbivores and carnivores, while the carbon isotopes tell mainly about the amount of protein in the diets from terrestrial versus marine ecosystems. 

The primary focus of isotopic studies on human bone has revolved around the distinction between consumption of C3 plant material and plant material Some years ago, it was discovered that the C3 (or Calvin) and the (or Hatch-Slack) photosynthetic pathways generated plant tissue with quite different abundances, an approximately 15 parts per thousand (0/00) difference in the isotopic ratio ( ) This isotopic difference between two types of plants is the main basis for most studies of human diets that have used stable isotopes of carbon as an analytical tool Most plants in temperate areas are of the C3 type, but corn (maize) is a plant and is of special interest to archaeologists because of the apparent dependence of many cultures on maize agriculture ... 

DeNiro, M. and Schoeninger M.J. 1983. Stable carbon and nitrogren isotope ratios of bone collagen variations within individuals, between sexes, and within populations raised on monotonous diets. Journal of Archaeological Science 10 199-204. 

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