Isotope dietary reconstruction

ISOTOPIC DIETARY RECONSTRUCTION FROM HUMAN BONE... 

Van Klinken, GJ. 1991 Dating and Dietary Reconstruction by Isotopic Analysis of Amino Acids in Fossil Bone Collagen—with Special Reference to the Caribbean. Ph.D. dissertation. University of Groningen, The Netherlands. 

The well-known saying you are what you eat has been taken almost literally in archaeology for the past 40 years, and dietary reconstruction has been attempted using trace element levels in bone mineral, and stable isotope studies... 

We have alluded above to the fact that dietary reconstruction from bone can be no more than a relatively long-term average, since in life bone is constantly remodelled. In general, a dietary reconstruction based on bone collagen is likely to represent the average diet of that individual over the last few years of life -perhaps up to as much as ten years before death, depending on the particular bone used. An extension of the isotopic dietary method is to use the differential information available within a single skeleton to study human lifetime mobility. This technique has been developed and exploited most clearly on historic material from South Africa (Sealy et al., 1995 Sealy, 2001 Cox et al., 2001). 

Diet and stable isotopes, western Mediterranean prehistory, 118-120 Dietary reconstruction from coprolites, human mtDNA extraction, Hinds Cave, Texas, 81 Dietary research through stable isotopes, principles and interpretation, 115-117 Dikgatlampi workings, Botswana, specularite sourcing, 465 Discriminant function analysis, INAA geochemical data, 466,469-477/... 

Bone tissue is created from the minerals and organic molecules that entered the body through drinking water and food and the chemistry of human bone holds information on the diet and life history of the deceased individual. Both the elemental and the isotopic composition of bone are important in studies concerned with dietary reconstruction. Elemental analyses focus on the mineral portion of bone, while isotopic studies are usually aimed at the organic part. Isotopic analyses are also used to study place of origin and past climate as recorded in tooth and bone. The role of archaeological chemistry in the study of prehistoric bones is discussed in further detail in Chap. 4 on Methods, and several examples are provided in Chap. 7, Environment and Diet. 

Cerling, T., Harris, J.M., Ambrose, S.H., Leakey, M.G. and Solounias, N. 1998 Dietary and environmental reconstruction with stable isotope analyses of herbivore tooth enamel from the Miocene locality of Fort Tsmaa. Journal of Human Evolution 33 635-650. 

Jim, S., Ambrose, S. H. and Evershed, R. P. (2004) Stable carbon isotopic evidence for differences in the dietary origin of bone cholesterol, collagen and apatite implications for their use in palaeodietary reconstruction. Geochimica et Cosmochimica Acta 68, 61 72. 

In order to reconstruct human diet from bone tissue, direct isotopic analysis of animal and plant remains from the same archaeological context is the most reliable way to detect isotopic shifts involving the whole ecosystem due to environmental variation. Since this is often impossible for the lack of these control samples, we have explored the use of 8I80 to assess the environmentally induced variation in 8I3C and 8ISN values from collagen and apatite, and assess the dietary information they represent. This can be done assuming a scarce nutritional role of marine resources and the absence of C4 crops, as seems to be the case in the western Mediterranean and specifically in the Sardinian Neolithic and Bronze Age. 

The results of these experiments permit more detailed reconstruction of the isotopic composition of prehistoric human diets. The bulk diet value can be reconstructed from the apatite value minus 9.4%c, and that of dietary protein can be reconstructed from the apatite-collagen difference (5 C Specifically, a difference of 4.4%c occurs when the protein and bulk diet have the same value. A spacing of less than 4.4%o indicates that dietary protein is isotopically enriched relative to whole diet. If the spacing is greater than 4.4%c, then dietary protein is isotopically lighter than whole diet. 

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