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pg 6 Diet and subsistent clearly has been linked to the "Explanatory Period" of archaeology which began in the 1960's (Willey and Sabloff 1974). This model primarily relyed upon ecological theory, with Kent Flannery as its main proponent. In addition, thenew paradigm was supported by man u who assumed the technico-economic level of culture to be the fundamental determinate of the social and ideational tiers of evolving cultural systems (Willey and Sabloff 1974:83
Gilbert and Mielke 1985). pg 7 In the late 1970's and particularly in the 1980's physical anthropology began to witness an resurrgence in the analyses of human skeletal remains and burial practices. The resurgence of research paleopathology also began to pop-up again fostered by new methods particularly in the area of paleodemography (e.g., Buikstra and Co 1980
Ubelaker 1982
Brothwell 1990). As a result of all of this, paleopathology and paleonutrition were bridged by investigations that explored association between past diseases, dietary patterns and environmental surroundings (Carlson et al 1974
Lallo et al 1977). Within this realm, attempts to document the biological efects of dietary change increased through investigations that assessed diachronic fluctuations in specific pathological lesions or nonspecific indicators of stress (Goodman et al 1980
Cohen and Armelagos 1984). The same period, marked by the "revitalization" of paleopathology and the grwoth of new paradigms in archaeology, also was characterized by an accelerating interest in trace elements and their effects on human health and disease. Research became increaingly focused on establishing the essential nature and general metabolic functions of trace elements among plants and animals (e.g., Schutte 1964
Underwood 1977
Prasad 1978). Investigators sought to delineate the upatke and efects of these substances on plant and animal tissues. It was the concern over one such element, Strontium-90, unintentionally led to the first strategy used by anthropologists for investigating paleodiet through elements analysis. pg 8 \uBasis for paleodietary application of Sr\u 1. premise that organisms absorb this element in quantities that vary inversely to the thei rank along the chain (Sandford 1992). a. So, plant-herbivors-carnivores, with omivores falling in between those represented by the two feeding extremes. 2. fluctuations and abundance of SR in various parts of plants, types of vegetation, and different ecosystms. a. grasses are less enriched than leafy plants b. aquatic environments, marine, rather freshwater ecosystems, provide higher quantities of SR relative to Ca. c. crustaceans have higher Sr than shellfish d. there are differences among some bony fish but as high as those of shellfish. 3. trophic levels relating to Sr levels in tissues is further reinforced by interactions betweent he former element and Ca (Sandford 1992). a. both alkaline earths, thus similar chemical attributes and functions b. most internally absorbed Ca and Sr are banked in dental and osseous tissue through ionic substitution c. quantities regulated by internal discriminatory mechanisms, in the gastrointestinal and urinary tracts of mammals, that normally enhance Ca absorption and Sr excretion. Similar means promote uptake of Ca, relative to Sr, by developing fetuses and nursing infants,and differential quantities of Sr, relative to Ca, in the tissues of pregnant and lactating females. pg 9 \uBasic principles involving Sr analysis and Sr/Ca ratios.\u 1. Aside from reconstruction of a single population, the most frequently encountered used of Sr are the evaluation of diachronic shifts in dietary patterns. (Schoeninger 1981, 1982
Sillen 1981
Katzenberg 1984). 2. the assessment of dietary differences accompanying social stratification (Schoeninger 1979
Blakely and Beck 1981
Geidel 1981, 1982). 3. the transition from breastmilk to solid food (Sillen and Smith 1984
Katzenberg articles) as well as dietary and physiological efffects of pregnacy and lactation (Blakely 1989) using skeletal Sr and Ca concentrations from prehistoric populations. The first pioneers of Sr and Sr/Ca suggested that Sr remained stable following death and postmortem deposition (Toots and Voorhis 1965
Parker and Toots 1980). This however, was abandoned later with the realization that postmortem alteration of skeletal Sr has been documented in a wide variety of archaeological and geochemical circumstances. Pg. 10 In multielemental analysis of dietary reconstruction, typically elements are chosen because of their presumed ability to discriminate between dietary dependence on vegetation as opposed to meat. Common elements are magnesium (Mg), manganese (Mn), and vanadium (V) are used with Sr and Ca as indicators of plant resources, while others, including zinc (Zn), selenium (Se), copper (Cu), and molybdenum (Mo) are employed to assess the animal protein component of the diet (Gilbert 1975
Geidel 1981, 1982
Edward et al 1984). Although biogenic and/or diagenetic forces can affect different elements in similar ways, knowledge of the properties, functions and distribution of each individual eletment, in both pre- and postmortem settings, is crucial for accurate interpretation. pg 11 The single-element approach has been used most extensively to investigate inadvertent past exposures to elements that are toxic in relatively small quantities. In this regard, most single-element investigations to date have focused on prolonged or acute exposure to lead (Pb) (Aufderheide 1989
Kowal et al 1989, 1991
Reinand ghazi 1992). Studies using lead can be useful in providing insights about the social and/or economic dimensions of culture, aspects of technology, occupational risk and/or social stratification. It can also be used by bioarchaeologists and forensic anthropologists as a means of separating commingled bones from individuals and the assignment of ancient or modern status to skeletal remains (Aufderheide et al 1988:934-935). for diagenetic studies (Waldron 1983, 1981
Reinhold and Ghazi 1992) nutritional deficiencies (Zaino 1968
Fornaciari et al 1983). Over the years there has been a noticable decrease in the amount of element studies in regard to relationships between nutrition and disease in past populations. 5 reasons: 1. emphasis placed on understanding and assessing diagenesis 2. limited backgrounds in trace element biochemistry and physiology 3. limited discussions to the assessment of primary nutritional deficiencies 4. relationship of specific trace elements to specific pathology often is unknown or unclear 5. bone physiology often is often not well understood by investigators pg 16 Stuart-Macadam (1985, 1987, 1992) has recently taken to task previous researchers for using porotic hyperostosis as a "nutritional stress indicator," noting that most investigators equate nutritional stress to dietary deficiencies. In addition, she argues that in most situations, Fe deficient diets are not a major cause of Fe deficiency anemia. She suggests that hypoferremia and, hence, porotic hyperostosis may reflect an adaptive physiological response to pathogenic burden. Insofar as Fe is conducive to some microbial reproduction and vigor, hypoferremia may act to combat certain foreign substances of parasitic, fungal, viral, or bacterial origin. pg 18-19 \bSkeletal Microstructure and Physiology\b There are at least three reason why an understanding of bone microstructure and physiology is vital to interpreting elemental data. 1. major and trace elements are fundamentally involved in processes such as growth, remodeling and maintenance of the skeleton. 2. a myriad of factors (e.g., hormonal immunological, dietary) that influence growth, modeling and remodeling may also affect elemental concentrations. 3. histological sections may prove to be a vital means of assessing diagenetic changes (Hanson and Buikstra 1987
Frost 1985
Schoeninger et al 1989). pg 20-23 \bClassification and Function of Elements\b trace elements make up less than 0.01% of the total body mass (Schroeder 1973). Major elements include: carbon (C), hydrogen (H), nitrogen (N), calcium (Ca), phosphorus (P), oxygen (O), potassium (K), sulfur (S), chlorine (Cl), sodium (Na), and magnessium (Mg) (Schutte 1964). Of these C,H,N,O comprise 96% of the weight of the human body (Saltment et al 1984), and with the addition of S and P, have been characterized as "moleculr building blocks of living matter" (Frieden 1972:150) because they are vital constituents of amino acids, sugars, nucleotides, purines, pyrimidines, and fatty acids. Ca, Mg, Na, and K lose electrons, thus forming the principal cations, or positively charged ions. In contrast, S, Cl, P gain electrons and functions as the principal anions or negatively charged ions. There are 15 trace elements that have been established as essential for animal life (Underwood 1977:1
Mertz 1981). iron (Fe), Zinc (Zn), copper (Cu), manganese (Mn) nickel (Ni) molybdenum (Mo), chromium (Cr), selenium (se) iodine (I) flourine (F), cobalt (Co), tin (Sn), Silicon (Si), vanadium (V), arsenic (As) These play 3 major roles in biological systems 1. are critical to catalytic reactions, often serving to attract substrates to enzymes 2. role of some trace metal ions is to donate or accept electrons in oxidation-reduction 3. acting as metalloproteins, some trace elements serve to bind, transport and release other elements, most frequently oxygen. pg 24 \bHomeostasis and the Skeleton as an Organ System\b
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