Palaeolimnological impacts of early prehistoric farming at Lough Dargan,County Sligo,Ireland

This study provides a unique method of inquiry for archaeological investigation with an aim to assess the intensity and effects of Neolithic and Bronze Age farming practices at Lough Dargan, northwest Ireland, through a multi-proxy analysis of a lake sediment core. Chironomid (non-biting midge fly) subfossils and lake sediment geochemistry (δ¹³C, δ¹⁵N and C:N ratios) were used to assess changes in limnological conditions through time. The limnological data were compared with macroscopic charcoal concentration and pollen data to examine the potential influence that early farmers had on a freshwater lake system within a prehistorically active catchment. Results from the chironomid analysis show that the first substantial period of agricultural activity in the early Neolithic (c. 3730–3190 BC) resulted in a temporary shift to more eutrophic lake conditions. There is evidence of animal husbandry with substantial levels of animal waste reaching the lake, leaving an imprint in the geochemical record of increased δ¹⁵N values and decreased δ¹³C values and C:N ratios during this time. The chironomid community reverted back to its pre-impacted state c. 3190 BC in response to a period of reduced farming (c. 3390–3000 BC) which eventually led to a distinct lull in activity, with possible cessation of farming from 3000 to 2700 BC. A return to eutrophic conditions coincided with the gradual return of agriculture, with more permanently altered lake conditions dominating from 2400 BC, even during a 250-year period of reduced human activity commencing at c. 1440 BC. Increased sedimentation rate, along with increases in δ¹³C, δ¹⁵N and C:N, the presence of chironomid taxa indicative of erosion, more eutrophic lake conditions and high concentrations of macroscopic charcoal all point to more intensive land use practices during the Bronze Age. Palaeolimnological data exhibited an immediate response to intensified farming during this time, and were especially responsive to pastoral farming due either to scale of activity or proximity to the lakeside. The success of this study demonstrates the effectiveness of palaeolimnological analysis in the investigation of prehistoric farming. This approach will help inform Neolithic and Bronze Age land-use practice and human–environment relations in the region, and highlights the potential for chironomid-based archaeological research.     

The fish of Lake Titicaca: implications for archaeology and changing ecology through stable isotope analysis

Research on past human diets in the southern Lake Titicaca Basin has directed us to investigate the carbon and nitrogen stable isotopes of an important dietary element, fish. By completing a range of analyses on modern and archaeological fish remains, we contribute to two related issues regarding the application of stable isotope analysis of archaeological fish remains and in turn their place within human diet. The first issue is the potential carbon and nitrogen isotope values of prehistoric fish (and how these would impact human dietary isotopic data), and the second is the observed changes in the fish isotopes through time. Out of this work we provide quantitative isotope relationships between fish tissues with and without lipid extraction, and a qualitative analysis of the isotopic relationships between fish tissues, allowing archaeologists to understand these relationships and how these values can be applied in future research. We test a mathematical lipid normalization equation to examine whether future researchers will need to perform lipid extraction procedures for Lake Titicaca fish. We also analyze a number of aquatic plants to better understand the range of isotopic signatures of the Lake Titicaca ecosystem. We use these data to better understand prehistoric human diet and the role that fish may have played in the past as well as potential changes in local lake ecology through time.     

翁牛特旗大营子冶炼遗址研究

大营子冶炼遗址位于赤峰市翁牛特旗五分地镇大营子村南侧的大山的北坡上,包含东西两区冶炼遗存。东区冶炼遗存年代较早,至迟在公元前1 400年已开始冶炼活动。铅同位素、微量元素示踪研究显示大营子冶炼遗址东西两区均使用了来自林西县大井古铜矿的多金属共生矿石,直接冶炼铜砷锡三元青铜合金。大营子冶炼遗址东区冶炼遗存的年代测定,获得了迄今为止最早的夏家店上层文化年代测定结果,为探讨辽西地区青铜时代考古学文化的演变提供了新的科学证据。     

Geographic variation in bone carbonate and water δO values in Mendoza,Argentina and their relationship to prehistoric economy and settlement

Questions of mobility, settlement pattern, and their relation to economic organization and resource use are central to ongoing work in central-western Argentina. Here we analyze geographic patterns in the distribution of 178 human bone carbonate δ¹⁸O samples, 46 human tooth enamel carbonate δ¹⁸O samples, and 48 water δ¹⁸O samples from throughout the Andean Cordillera and Monte Desert and evaluate their implications for prehistoric mobility and economy. We confirm and refine previous generalizations regarding a highland/lowland dichotomy in water δ¹⁸O values and show that the range of human carbonate δ¹⁸O values generally reflect available water sources. While there is little within-lifetime change in patterns of water use, we show that most individuals have stable isotope signatures consistent with water use from multiple areas or areas other than where they were ultimately interred. These data indicate high levels of residential mobility, and we conclude by discussing their implications for our understanding of regional prehistory.     

In situ oxygen isotope micro-analysis of faunal material and human teeth using a SHRIMP II: a new tool for palaeo-ecology and archaeology

A Sensitive High Resolution Ion MicroProbe (SHRIMP II) has been used to make high spatial resolution in situ micro-analyses of oxygen isotopes in fish otoliths, and teeth from fossil herbivores and a Neanderthal. Large intra-tooth variations in the oxygen isotopic composition (up to 9‰) were observed in the enamel of herbivores from the Neanderthal fossil site of Payre, consistent with preservation of seasonal cyclicity. The range of isotopic compositions observed in Neanderthal tooth enamel was much smaller (∼3‰), possibly the result of a longer enamel maturation time averaging out variability. An archaeological otolith from a Preceramic site in Northern Peru exhibited marked changes in δ¹⁸O over life, due either to the fish occasionally migrating from the sea to a lower salinity habitat, or to short-lived rises in sea water temperature. A fish otolith from Australia's Willandra Lakes World Heritage Area showed clear seasonal variations, but also a general trend towards isotopically heavier and more saline water, as indicated by higher δ¹⁸O and Sr/Ca values resulting from increased evaporation. The results of these case studies are compared to results of oxygen isotope analysis using more conventional methods and demonstrate the ability of the SHRIMP II to provide precise high spatial resolution in-situ oxygen isotope analyses of a variety of biogenic materials. This approach has major advantages over conventional methods. It can provide rapid, micro-scale isotopic analyses of sub-permil precision without the need for chemical preparation of the sample.     

Influence of seabird guano and camelid dung fertilization on the nitrogen isotopic composition of field-grown maize (Zea mays)

Organic fertilizers have the capacity to alter the nitrogen isotopic composition of plants. Camelid dung and seabird guano are two potentially important fertilizers in the agricultural systems of western South America, particularly Peru and Chile. This paper presents isotopic data (δ¹³C and δ¹⁵N) from field grown plants (maize, Zea mays) fertilized with the following four treatments: CO (control, no fertilizer applied), AS (ammonium sulfate, a chemical fertilizer), DU (camelid dung), and SG (seabird guano). Plants were grown in experimental plots in the Virú Valley, northern Peru. Plants fertilized with the chemical fertilizer presented very similar isotopic compositions compared to the control. Conversely, the camelid dung fertilized plants were characterized by higher δ¹⁵N values compared to the control plants (by 1.8 to 4.2‰ depending on the plant part). The seabird guano fertilized plants were greatly enriched in ¹⁵N in comparison to the control plants (by 11.3 to 20.0‰). The results of this study have important implications for the reconstruction of human diet using isotopic data derived from bone collagen and related tissues, particularly in the prehispanic Andes, but also in Europe and North America during the 19th century, when Peruvian seabird guano was used extensively. Specifically, the interpretation of the relative contributions of plant and animal protein to the diet on the basis of bulk isotopic compositions of bone collagen (or similar tissues) may be confounded by camelid dung fertilization if the carbon isotopic compositions of the two sources are similar. Likewise, the interpretation of the relative contributions of maize and marine protein may be confounded by seabird guano fertilization.     

Archaeological excavations at Bosutswe,Botswana: cultural chronology,paleo-ecology and economy

Excavations at the site of Bosutswe on the eastern edge of the Kalahari Desert in Botswana have uncovered over 4 m of deposit ranging in age from CE 700 to 1700. Our research has produced quantitative and qualitative measures of the material and ecological dimensions that structured the everyday actions and behaviors through which social identities were constituted, maintained, and transformed during the period when the polities of Toutswe, Mapungubwe, Great Zimbabwe and Khami rose to power. By examining the material dimensions that underlay shifting relations of production, exchange, and social stratification we are able to contextualize the social judgments that ascribed value to material goods and food ways, while specifying the ways these were used to create and naturalize social relationships and power differentials. Stable isotope analyses, combined with evidence of vitrified dung, further enable us to suggest changes in herd management strategies used by the inhabitants of the site to compensate for ecological changes brought about by long-term occupation, while at the same time enabling them to economically tie subordinates to them as social divisions became more rigidly defined after CE 1300. The cultural and economic changes that took place at Bosutswe thus directly impact our understanding of the social transformations that immediately preceded contemporary configurations of ethnicity in Botswana.     

Human biology in the Classic Maya collapse: Evidence from paleopathology and paleodiet

We review evidence from human biology—paleopathological and isotopic paleodietary studies on ancient Maya skeletons—to assess the validity of ecological models of the Classic Maya collapse, in which elevated disease and deteriorating diet are commonly assumed. To be upheld, the health arguments of ecological models require that the Maya disease burden (1) was greater than that for many other societies and (2) increased over the span of occupation. The dietary argument requires (1) consistent change in diet from Preclassic and Early Classic Periods to the Terminal Classic and (2) increasing social divergence in diet. A correlation between diet and disease is necessary to link these arguments. Neither pathology nor isotopic data consistently support these criteria. Instead, it appears that local environmental and political factors created diversity in both disease burden and diet. In view of the human biological data, we are skeptical of ecological models as generalized explanations for the abandonment of Classic Maya sites in the southern lowlands.