| Abstract: |
pg 115-116 STABLE ISOTOPE GEOCHEMISTRY OF HUMAN BONE Norr (1990) studied the isotope geochemistry (13C/12C and 15N/14N) of human skeletons from central Pacific Panama (for a discussion of methods, see Price 1989). Elsewhere, she has discussed the potential of the nitrogen and carbon pathways for identifying different dietarv foci among human populations from lowland tropical America {Norr 1995}. When the two pathways are applied in tandem, variations in the dietary inputs of marine foods and C4 Plants can be estimated. Unless wild panicoid grasses and CAM cacti were regular dietary sources, which is unlikely in central Pacific Panama, maize was probably the only C4 plant consumed during the time period under scrutiny Norr {!Norr 1990} originally processed only bone collagen. Since then, she and Ambrose {Ambrose and Norr 1993} have conducted experimental research with laboratory rats on carefully controlled diets. This work has demonstrated that the carbon isotope composition of bone collagen disproportionately reflects that of dietary protein and is not uniformly intermingled with those of carbohydrates and lipids. In contrast, bone apatite carbonate 13C values, closely follow the carbon isotope values of the whole diet. The joint evaluation of 15N, and both collagen and apatite 13C val enabled Norr {!Norr 1995} to detect differences between the diets of the two neighboring sites of different ages: Cerro Mangote and Sitio Sierra. Norr's data highlight a paradox (Figure 5): Cerro Mangote's population, more than 4000 years older than neighboring Sitio Sierra's, consumed slightly more C4 plant foods and less marine protein, even though Cerro Mangote was situated 1.2-5.5 km from the active coastline about 4000 B.C. In contrast, Sitio Sierra was 12-13 km inland between 25 B.C. and A.D. 1100. To what extent do dietary macro remains from Cerro Mangote and Sitio Sierra confirm or contradict Norr's isotope data? pg 120 From these data, there emerges a consensus about the nature and trajectory of human adaptations to and modifcation of the seasonally dry forests of ...... Populations, initally small and scattered, gradually became larger. Farmers resorted to slash-and-burn techniques on extensive tracts of premontane forest. Maize, which is not a native crop, was probably first used between 5000 and 3000 B.C.
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