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1.
Shell samples of the marine gastropod Turbo sarmaticus have been examined to assess their potential for electron spin resonance (ESR) dating. The shells were found to be composed of aragonite. ESR analysis shows the presence of three radiation sensitive peaks. Equivalent dose (ED) values for two of the peaks have been determined for thirteen samples. When the two sets of ED values are plotted against each other, four distinct clusters are found that appear to represent four different age groups. The apparent age groups determined here are consistent with the stratigraphic record of the sites.  相似文献   

2.
We undertook combined stable carbon, nitrogen and sulphur isotope analysis of marine and terrestrial faunal remains from two prehistoric coastal shell middens in Denmark. The aim of the investigation was to establish whether sulphur isotopes were useful in discriminating terrestrial and marine consumers in this region. We found that sulphur isotopes do separate marine and terrestrial fauna but, contrary to our expectations, we observed a negative correlation between δ34S and δ13C values for marine fauna. We conclude that similar studies over a broader geographical range are needed before sulphur isotopes can be reliably used to study coastal resource exploitation.  相似文献   

3.
The skeletal remains of 18 individuals interred at the ancient Maya site of Caledonia (100 to 1000 C.E.), located in the Cayo District of Belize, w ere sampled for stable carbon and nitrogen isotope analysis in order to reconstruct their diet. Stable carbon and nitrogen isotope ratios in 18 bone collagen samples and stable carbon isotope ratios in bioapatite from 15 bone and 6 tooth enamel samples were assessed. Small sample sizes precluded the assessment of dietary variation with respect to age, sex, social status or time period among the Caledonia Maya. However, the sampled individuals consumed a varied diet consisting of maize, supplemented with some C3 plants, terrestrial herbivores and/or lower order freshwater resources such as snails and molluscs and possibly maize‐fed animals. This dietary variability with an emphasis on maize is unsurprising given the biological diversity surrounding the site and the known importance of this crop to the ancient Maya. As expected, the isotopic values from Caledonia are similar to those from nearby sites from similar time periods. However, four individuals exhibit a marine dietary signature, possibly indicating inland trade of marine resources from coastal sites, or the migration of coastal people to Caledonia. This study demonstrates the validity of sampling small, fragmented collections from minor Maya centres in order to gain valuable insight into ancient Maya dietary practices. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

4.
A number of recent studies of the UK coastal environment have assessed the 14C marine radiocarbon reservoir effect (MRE) via quantification of ΔR values for several periods throughout the Holocene using marine mollusc shells. However, none have employed fish bone as the marine sample, and the importance of being able to use this material as a reliable dating tool is evident when considering the boom in the British fish trade during the first millennium AD, the so-called ‘fish event horizon’, and the corresponding volume of fish remains that appear in the archaeological record from this time. This study compares ΔR values derived using the multiple paired sample approach employing burnt cereal grain (Hordeum sp.) as the terrestrial sample and either fish bone [North Sea cod (Gadus morhua)] or marine shell [limpet (Patella vulgata)] as the marine sample. The results show a general trend of increasing ΔR for the fish bone compared to shell, however, the differences are not statistically significant when the standard error for predicted values is used as the measure of variability in the ΔR values.  相似文献   

5.
Paleoamerican colonization models have emphasized the importance of coastal zones for provisioning hunter gatherers with a diverse range of subsistence resources. This article expands on recent research by Lowery et al. 2012, and presents a model to explain the distribution of Clovis points across the Atlantic slope of Eastern North America. Marine transgression since the last glaciation has submerged large tracts of the Atlantic continental shelf. Global bathymetric data was used to estimate the Clovis age shoreline from Delaware to Florida. Clovis biface data for modern coastal areas, obtained from the Paleoindian database of the Americas, was compared to the slope of the paleo-shoreline to predict coastal zone preference. Results indicate a relationship between point distribution and coastal zone type. Areas where major rivers with high-quality tool-stone intersect broad coastal zones served important roles to Clovis subsistence adaptations. The potential exists for early Paleoamerican sites along the continental shelf submerged beneath 55–75 m of the Atlantic Ocean. Modern coastal regions with high densities of Clovis points may serve as analogues for identifying earlier sites that have been submerged as a result of marine transgression.  相似文献   

6.
Three newly discovered prehistoric sites on the east coast of the United Emirates (UAE) are described. All are located on surfaces of Pleistocene carbonates or rock shelters that are generally rare along the eastern coast of the Gulf of Oman. Aqqah 1 (Le Meridien al Aqqah Beach Resort), the most important and best preserved of these sites, is a partially collapsed rock shelter with an exposed section, lithic finds and marine molluscs. Deriving an exact date from the material present is difficult because of a lack of comparanda. A bifacial fletched arrowhead made of yellow jasper and the lithic debris of five different raw materials as well as an undecorated ceramic fragment might suggest a date in the Late Neolithic or Early Bronze Age. The presence of many marine bivalves and snails with operculae, which differ from recent coastal species, indicates the collection and consumption of living molluscs by the prehistoric population of Aqqah. Nearby burials may be related to the rock shelters.  相似文献   

7.
Prehistoric molluscan assemblages provide insights into long-term patterns of human landscape use, environmental change, and human impacts to marine resources. The investigation of forager decision-making regarding the selection of certain mollusc taxa and/or the exploitation of particular habitats is fundamental to understanding human-environment interactions in the past, and is relevant for understanding trajectories of human impacts to the intertidal zone in coastal settings. We document variability in the collection of molluscs at two archaeological sites on Ebon Atoll, Republic of the Marshall Islands: one on a windward, intermittently occupied islet, and the other on a permanently inhabited leeward islet. All molluscan taxa were assigned to a range of habitats within a hierarchical classification scheme for intertidal marine environments. The relative abundance of taxa from each habitat was used as a proxy for forager decision-making. We report a generalized, non-selective, foraging strategy focused on gastropod taxa from the high intertidal and supratidal. These results indicate that rather than focusing intensively on select taxa, intertidal foragers targeted particular marine habitats, taking advantage of the predictable behaviors of the molluscs that inhabit them.  相似文献   

8.
The ESR dating method requires to describe the evolution of the ESR signal intensities vs. increasing gamma doses, then to extrapolate the equivalent dose of radiation received by the sample since its deposition using mathematical fitting. The function classically used to describe the growth curves of ESR aluminium signal in quartz was recently discussed and challenged for Lower Pleistocene sediments. In the present work, some alluvial sediments sampled in Upper Pleistocene fluvial terraces of the Yellow River system (China) permit us to test the application of another extrapolation function (linear + exponential) recently proposed for Lower Pleistocene sediments. The equivalent doses obtained here for the recent deposits of the Yellow River system and the corresponding ages are promising and indicate the potential of ESR to date quartz deposits from Upper Pleistocene times.  相似文献   

9.
Radiocarbon dates on marine shells have not been used as extensively as charcoal or bone dates for the setting up of absolute chronologies because interpreting these dates is complicated by the marine radiocarbon reservoir effect. Nevertheless marine shellfish were used widely at least during the Holocene and their shells are abundant and usually well preserved in archaeological deposits located near shorelines. Consequently prior research concerning the oceanographic conditions and the marine radiocarbon reservoir effect of a particular coastal area is needed in order to set up reliable chronologies for that region. Values of regional marine radiocarbon reservoir effect – ΔR – of coastal waters off Atlantic Iberia, some of its variability along the Holocene and its correlation with the upwelling phenomenon were determined during previous research. More data related to the ΔR values for western Portuguese coastal waters during the Late Neolithic and the Chalcolithic, a time interval badly sampled in previous research, were recently obtained. These values can be compared with ΔR values already determined for the Gulf of Cadiz. Besides the importance of these values for a better knowledge of the palaeoceanography and palaeoclimatology of Atlantic Iberia, from now on archaeologists can set up reliable chronologies for Late Neolithic and Chalcolithic contexts using marine shell samples of that origin for radiocarbon dating.  相似文献   

10.
We have obtained ESR ages on 18 teeth from archaeological levels AH16-AH27 exposed at the east profile in compartment E at Karaïn Cave. This sequence exhibits a transition in lithic assemblage from a Classic Charentian to a Karaïn (Zagros-type) Mousterian between levels AH27 and AH25, and two calcite-cemented soils at levels AH22 and AH16 which have been interpreted as climatic warm phases. Since we found no systematic increase in tooth ages with depth, we assigned this sequence a mean early uptake (EU) age of 108 ± 23 ka and mean linear uptake (LU) age of 121 ± 27 ka, on the basis of 37 subsamples from 16 teeth. In this site, the precision of individual tooth ages suffered little from the problems associated with uranium uptake. However, this advantage was offset due to uncertainties arising from the rather inhomogeneous nature of the enclosing strata which contained various sizes of limestone blocks with intervening sediment. This led to difficulties in ascribing a precise annual gamma radiation dose to individual teeth in such a "lumpy" gamma radiation field. Considerable scattering of the individual tooth ages occurred mainly because the annual gamma dose comprised greater than 50% of the total annual dose to the individual teeth. On the basis of the ESR dating results, we infer that deposition of the two different lithic assemblages and both the penultimate and the final climatic warm phases at Karaïn probably occurred during oxygen isotope stage 5. We also conclude that these lithic assemblages are significantly different than contemporaneous Levantine Mousterian industries which occur about 700 km to the southeast.  相似文献   

11.
The role of coastal resources in the subsistence strategies of Palaeolithic human populations has only recently become an important topic in Old World archaeology. Information on the exploitation of these resources, both as foodstuffs and symbolic elements, can be used to infer the emergence of modern human behaviour as well as to track the diversification and intensification of human diet over time. The excavations carried out at El Cuco rockshelter, located in northern Spain have provided evidence for the exploitation of marine resources during the Early Upper Palaeolithic. The accumulation of Patella shells at El Cuco provides the largest accumulation and the first clear evidence of collection and consumption of molluscs during the Aurignacian on the Atlantic Façade of Europe. A deposit of ornamental shells appeared in a very homogeneous context dated to the Gravettian, suggesting that the shells belonged to the same item. The analysis of this evidence has allowed us to conclude that marine resources were systematically used at least from the beginning of the Upper Palaeolithic in the region. However, a comparison with the Mesolithic shows that intensive shellfish gathering did not occur until the end of the Upper Palaeolithic. Regarding the ornaments, it is interpreted that the identified shell beads were used as social or personal status markers.  相似文献   

12.
Quaternary stratigraphy and sea level changes have been extensively investigated in many areas of the Mediterranean. However, numerical dating of coastal deposits and the associated paleoenvironmental information are limited for the coasts of Cyprus, principally based on radiometric and radiation-exposure geochronological techniques on fossils which bear a range of limitations and uncertainties. As such, optically stimulated luminescence (OSL) dating techniques are deemed to be the most suitable in direct dating of the coastal sediments of Cyprus. In the southeastern Cyprus, coastal dunes (aeolianites) now forming elongated ridges appear as morphological features running parallel to the current shoreline presenting an indicator of sea level and climate changes of great paleoenvironmental significance. We present our first chronological results for the exposed aeolianites and underlying littoral deposits formed along the southeastern coastal Cyprus ranging from 78.4 ± 9.9 to 56.2 ± 7.4 ka. The post-infrared–infrared stimulated luminescence (pIR-IRSL) revealed that dune formation took place during the marine isotope stages (MISs) 3, 4, and possibly 5a. Late Holocene reworking is proposed for a distinctively isolated dune with an age of ~1.3 ka ago. This study also showed that pIR-IRSL dating of feldspars may be a reliable alternative to quartz OSL dating when the quartz luminescence characteristics are unsuitable.  相似文献   

13.
The Rabat-Témara region of the Moroccan Atlantic coast reveals a succession of Quaternary palaeobeaches. This coastal area is dotted with numerous prehistoric caves. The study of the Upper Pleistocene coastal landscape associated with these caves is of paramount importance in the knowledge of human population subsistence. During the Upper Pleistocene, the ocean level changes drastically influenced the coastal geomorphology as well as the fauna assemblages. The chrono-lithostratographical analysis of the coastal sedimentary formations allows the distinction of three sequences rich in marine fauna. These sequences date from MIS 11 to MIS 5. The identification of malacofauna species from these deposits revealed 39 species, along with Bryozoans, Crustaceans, and Echinoids. These assemblages show a constant fauna cortege highlighted by the dominance of the amphi-Atlantic species Stramonita haemastoma. This species shows an increase in the number of specimens in the uppermost part of marine deposits, probably in relation with a climate warming in the MIS 5. This fauna of both intertidal rocky substrates and sandy substratum indicates environmental conditions close to the present-day Rabat-Témara coastline. As in other coastal locations of Africa from MIS 5, the Middle Stone Age Homo sapiens population benefitted from a littoral environment rich in coastal resources. Comparison between thanatocenoses and archaeological records allows us to identify both species available for Middle Stone Age population and those preferred for human use.  相似文献   

14.
Nitrogen isotope ratios in tissues are often used to aid in the reconstruction of the marine component of diets in past populations. Elevated δ15N values normally found with high trophic level marine resource consumption can, however, also be mimicked by physiological conditions (breastfeeding, pathological states affecting nitrogen balance), climate (aridity), and anthropogenic environments (manuring). This paper presents a pilot study testing whether bromine concentrations can provide a tool for teasing apart possible causes of variation in nitrogen isotope ratios. Blind analyses of bromine in archaeological samples correctly identified individuals derived from coastal vs. inland regions and high vs. low marine consumption time periods. Thus, bromine can provide an important supplement to other isotopic analyses of diet.  相似文献   

15.
The number of studies using trace elements as indicators of diet has increased with time, but the majority have used few elements and a small sample. The present study has as a principal objective a multi-element analysis of diet in a large sample in which diagenetic changes have been shown to be unimportant. The analysis was made using concentrations of seven elements—Sr, Ba, Mg, Cu, Zn, V and Ca—in 197 individuals from the necropolis of ‘S' Illot des Porros’ (Majorca, Spain). The results show that these individuals would have had a mixed diet with a high meat component, principally of marine origin (molluscs and fish), but with an important consumption of seeds and cereals and a low proportion of vegetables.  相似文献   

16.
California’s Channel Islands were home to some of the most distinctive Native American peoples along the Pacific Coast. Never connected to the mainland during the Quaternary, the Channel Islands have an impoverished terrestrial flora and fauna, but some of the richest and most productive marine environments in the Americas, including diverse kelp forest, intertidal, and offshore marine habitats. Native Americans occupied the Channel Islands for roughly 13,000 calendar years until the early nineteenth century, providing one of the longest and best preserved records of maritime hunter-gatherers in the Americas. We provide an overview and analysis of Channel Islands archaeology, from the relatively mobile peoples who colonized the islands during the Late Pleistocene to the complex hunter-gatherers documented by early Spanish explorers. Our analysis demonstrates the importance of Channel Islands archaeology for enhancing knowledge on a number of broad anthropological issues, including coastal and aquatic adaptations, seafaring, cultural complexity, trade and exchange, and ancient human impacts on the environment.  相似文献   

17.
In recent years, a team at the Geology and Paleogeography Unit, Marine Sciences Institute, University of Szczecin, has been performing geological, geochronological and paleogeographic surveys in (i) the Szczecin Lagoon and Świna Gate Sandbar and (ii) the estuary section of the Rega river valley near Mrzeżyno. These studies have helped to examine and identify not only the distribution of fossil marine sediments but also their lithological and sedimentological characteristics. The age of marine ingressions and regressions in the coastal zone of the Pomeranian Bay were determined using approximately 170 radiocarbon assays.  相似文献   

18.
The marine trophic levels targeted during Swift Creek (AD 300–700) and Savannah (AD 1200–1500) occupations at the Cathead Creek site (9Mc360) and at two sites from the Kings Bay Locality (9CAM171a, 9CAM177), coastal Georgia, USA, differ in a consistent temporal and spatial pattern. Vertebrate and invertebrate remains from these three coastal sites contain similar suites of estuarine animals. However, Swift Creek peoples at these distinct hydrological settings obtained more biomass from fishes and less from molluscs compared to the subsequent Savannah occupants. The two Swift Creek faunal collections are less rich, more diverse, and more equitable than the two subsequent Savannah collections regardless of location. Furthermore, the mean trophic level is higher in the Swift Creek collections compared to the Savannah ones at both locations. These observations apply to both biomass and Minimum Number of Individuals. These differences likely are defining characteristics distinguishing the Swift Creek and the Savannah economies. More research is needed to determine the extent to which these temporal and spatial patterns are attributable to environmental and cultural variables.  相似文献   

19.
Dental calculus extracted from the teeth of 28 prehistoric human skeletons from coastal and valley archaeological sites in northern Chile that date from the Archaic period (∼2300 BC) to the Late Intermediate period (AD 1476) was analyzed for stable isotope (δ15N, δ13C) compositions. δ15N compositions were extremely heavy (+17.8 to +33.1‰), but comparable to some studies using conventional human biomaterials (hair, nail, muscle) at other prehistoric sites in northern Chile. There was a negative correlation between δ15N and δ13C for coastal sites, but a positive correlation for valley sites. Results for the valley sites point to a diet that was influenced by marine resources throughout all time periods. The unusually heavy δ15N values for the coastal sites require a dietary component with a δ15N composition significantly heavier than that of marine resources. The hyper-aridity at the study area (mean annual rainfall of 0.5–0.6 mm/year) is a likely contributing factor to the production of heavy δ15N values, but is unlikely to account for the heaviest δ15N values (>+30‰). One possible explanation for the heaviest δ15N values is that dietary components were impacted by isotopically-heavy guano, which is abundant in the region. Guano may have been used as a fertilizer during crop cultivation at the onset of the Formative period, continuing through the Historic period after Spanish contact. The indirect impact of guano from abundant bird habitats in the region may have influenced wild foodstuffs harvested throughout the pre-agricultural period. Results provide support for the utility of dental calculus as a proxy for obtaining stable carbon and nitrogen isotope signatures for use in paleodietary studies.  相似文献   

20.
The exploitation of marine resources in Prehistory has traditionally been regarded as insignificant, at least until the late Upper Pleistocene. However, in recent years the systematic study of archaeofaunal remains with a marine origin has widened our knowledge of the role they played among groups of hunter–gatherers in Europe. This paper analyses the available data about the evidence for the exploitation of the different marine resources (molluscs, birds, mammals, crustaceans, echinoderms and fish) that have been recorded at archaeological sites in Cantabrian Spain in the late Pleistocene and early Holocene.With the information currently available, it is clear that although it is in the Mesolithic when archaeozoological remains with a marine origin are found most often, the exploitation of these resources in the region began in the Early Upper Palaeolithic.  相似文献   

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