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1.
We have studied the mineral composition of the gloss and the ceramic body of three pieces of Attic Greek pottery by applying the technique of high-resolution powder diffraction using synchroton X-rays. The measurements were performed on Stations 2·3 and 9·1 at the Synchrotron Radiation Source, Daresbury Laboratory. High quality powder patterns from the bulk of the ceramics and from the gloss surfaces have been obtained. The diffraction results show interesting variations of mineral composition between the gloss of the different sherds as well as variations between the bulk and the gloss. This makes phase identification and comparison between different fabrics less ambiguous. Spinel minerals are present in the gloss which are absent in the main body of the ceramics. Diffraction lines from one surface match the patterns of hematite, magnetite/maghemite and hercynite, while solid solutions of spinel structures appear to be present in the gloss layer of another sample. Crystallite particle sizes and lattice parameters of the minerals in the gloss layer have been accurately determined. Supplementary scanning electron microscopy (SEM) reveals the gloss thickness to be approximately 20 μm but with variations down to 5 μm. Analysis of the diffraction profile for the hematite component reveals a particle size in the order of 0·027 μm.  相似文献   

2.
The carbon isotope fractionation between tooth enamel bioapatite, breath CO2, and diet was measured for voles, rabbits, pigs, and cattle on controlled diets. The measured fractionation (expressed as isotope enrichment ɛ*) between enamel and diet was 11.5 ± 0.3‰, 12.8 ± 0.7‰, 13.3 ± 0.3‰, and 14.6 ± 0.3‰ for these respective species. There is a 1:1 correlation between ɛ*breath–diet and ɛ*enamel–diet (r2 = 0.94, p < 0.01), whereas our data do not resolve significant inter-species differences in ɛ*enamel–breath. These findings are consistent with the hypothesis that inter-species differences in ɛ*bioapatite–diet are primarily a result of differences in digestive physiology, rather than differences in the magnitude of fractionation between mineral and body fluid.  相似文献   

3.
Stable isotope signatures of both human and non-human animal bone samples indicate that Neolithic farmers of the Yellow and Wei River basins in China potentially cultivated millet for two reasons: as a staple for human consumption and as fodder for domesticated animals, specifically pigs, dogs, and perhaps chicken. Bone samples were analyzed from four Neolithic sites: Jiangzhai, Shijia, Xipo, and Kangjia, spanning the time period from 7000 to 4000 years ago. A combination of very high carbon isotope ratios (δ13C = −7.7 ± 0.4‰) and low nitrogen isotope ratios (δ15N = 7.5 ± 0.5‰) in samples of Xipo pig and dog bone suggests that these monogastric animals consumed substantial quantities of C4 plants, almost certainly millets. In fact, the proportion of C4 plants in animal diets appears to have been even greater than that in human diet. Stable isotope values (δ13C = −10.0 ± 0.8‰; δ15N = 8.3 ± 0.5‰) of human bone collagen recovered at Jiangzhai and Shijia indicate a staple role for millets, as well as the consumption of both wild and other non-C4 domesticated plant foods. As millet agriculture and animal husbandry apparently depended on one another, a strong mutualism between them was likely established in northern China during the Neolithic. We propose that variable redistribution of agricultural products between humans and animals, depending on the availability of wild resources and annual fluctuations in agricultural output, helped ensure the stability of Neolithic human subsistence in the Yellow and Wei River basins.  相似文献   

4.
This paper presents the first chronometric dates for sediments that contain a Mousterian industry in Dalmatia (south Croatia). Electron spin resonance (ESR) dating was conducted on two teeth from the Mousterian level E1 at the site of Mujina Pećina. Additionally five bone and one charcoal sample from five different strata of origin at this site were dated by accelerator mass spectrometry (AMS). Assuming 30% moisture for both the gamma and beta dose rate calculations, the mean LU ESR age estimate is 44±5 ka for level E1, which is statistically indistinguishable from the mean EU ESR age estimate of 40±7 ka. A single, uncalibrated 14C age from the E1/E2 interface yielded an age estimate of 45,170 +2780/−2060 years bp while the mean of the five samples from overlying Mousterian levels is 39±3 ka. The true (calibrated) age of this mean is about 42 ka, which means that the entire stratigraphic profile in Mujina Pećina apparently was very rapidly deposited, and that the ESR age, regardless of uptake model is in good agreement with the calibrated 14C mean age. Temporally, Mujina Pećina overlaps with Pontinian Mousterian sites in west-central Italy and Vindija level G3 from northwestern Croatia. However, there are notable differences between the Mousterian industry from Mujina Pećina and these other sites. Collectively, the Croatian sites yield important evidence on the adaptation of European Mousterian people.  相似文献   

5.
6.
Two Pliocene archeological sites, LA1 and LA2C, reported from Lokalalei, west of Lake Turkana in Kenya, were previously placed at approximately the same stratigraphic level. LA2C actually lies about 20 m higher in the section than LA1, and is perhaps as much as 100,000 years younger in age.  相似文献   

7.
Microcracks produced during the manufacture of stone tools may harbour ancient biological residues. Our studies test this hypothesis using light, scanning electron, fluorescence, and confocal microscopy to characterize microcracks produced in obsidian microblades by pressure flaking. Cell-sized fluorescent latex beads penetrated microcracks to depths exceeding 50 μm below the microblade surface. Fluorescently labelled blood protein and DNA were trapped in microcracks within 5 min of exposure. Washing artifacts with water did not remove blood residues from microcracks. However, 60–80% of trapped blood protein and DNA were released by an 18-hour incubation in 4M guanidine hydrochloride or by sonication in 5% ammonium hydroxide. These experiments suggest that residues trapped in artifact microcracks represent an important and often overlooked source of ancient DNA and protein.  相似文献   

8.
The Sincu Bara site in Senegal is one of the most famous archeological sites in Western Africa. Here we present the results of a multi-proxy study that combined microscopic analyses, carbon content, stable carbon isotope (δ13C) and radiocarbon (14C) measurements. This investigation exhibits a chronological framework in two phases: from 400 yr AD to 650 yr AD and 650 yr AD to 900 yr AD. Furthermore, it shows that besides basic potteries, some potsherds are notable for a temper exclusively made with human-harvested C4 plants. Finally, the 14C analysis performed on the organic slip strongly indicates the use of bitumen or bitumen-derived products for red slip preparation. This suggests the establishment of trade relationships with Nigerian and/or Trans-Saharan populations as early as 400 yr AD.  相似文献   

9.
Attirampakkam, an open-air stratified Palaeolithic site in southeastern India is the focus of ongoing studies to investigate the nature of Lower and Middle Palaeolithic occupation in relation to changing Pleistocene environments. The paucity of faunal or palaeobotanical remains at the site required the use of rock magnetic properties (χlf, χfd, χfd %, χARM, SIRM, χARM/SIRM, SIRM/χlf, χARM/χlf, χARM/χfd, S-ratio, HIRM and HIRM/IRM300mT) as proxies for deciphering the palaeoenvironments and palaeoclimates of the region. Rock magnetic data from stratified deposits within excavated trenches show that the bulk of the sedimentation was intermittent with no subaerial exposure of sediments for long periods, and points to fluctuating wetter and drier climates associated with the Acheulian to Late Middle Palaeolithic levels. There is a general trend towards a wetter climate from Layer 5 upwards. Layer 7 offers evidence of bacterial magnetite (χARM/χlf > 40 and χARM/χfd > 1000), suggesting the onset of micro-anaerobic environments as a result of floods. Greigite is indicated in Layer 5 (SIRM/χlf > 30 × 103 A m?1), which indicates a reducing environment. Layer 2 represents an arid climate (higher proportion of haematite and a coarser magnetic grain size). Layer 1a again is indicative of an arid climate (presence of calcrete, magnetically “hard” minerals and coarser magnetic grain size). Results indicate that the southeast coast of India experienced a mostly dry tropical climate during the Pleistocene. The detected occurrence of a few notably more arid intervals did not disrupt occupation of the site by successive groups of hominins.  相似文献   

10.
We studied the presence of immunoglobulin G (IgG) in equid fossil bones from Venta Micena (Granada, Spain), dated at 1·6 Myr old, and from Atapuerca (Burgos, Spain) (0·12 Myr), and in ostensibly hominid fossils VM1960 and VM3691 (1·6 Myr) from Venta Micena and CV1 and CV2 (1·4 Myr) from Cueva Victoria (Murcia, Spain). Samples taken from the specimens were crushed to a fine powder and their mineral structure was dissolved in an ethylenediaminetetracetic acid (EDTA) solution. Fossil extracts were tested with antibodies against human IgG and against horse IgG with two independent immunological methods: dot-blotting (DB) and a modification of this latter method: quantitative dot-blotting (QDB). IgG was detected by DB and was quantifiable by QDB in some of the fossils tested. Equid fossils from Atapuerca and Venta Micena gave stronger reactions with the antibodies against horse IgG than with the antibodies against human IgG. Fossils VM3691 and VM1960 reacted more strongly with the antibodies against human IgG than with antibodies against horse IgG, whereas no IgG was detected in fossils CV1 and CV2. These findings show that species-specific IgG can be detected in fossils as old as 1·6 Myr. The immunological analysis of fossil proteins may help to solve palaeontological controversies.  相似文献   

11.
The Grande Aula, or Great Hall, of the Markets of Trajan (AD 96 to 115) is an intact example of the domed, concrete architecture of imperial Rome. Petrographic, x-ray diffraction, chemical, and SEM analyses demonstrate that wall mortars contain Pozzolane Rosse volcanic ash aggregate (harenae fossiciae) and strätlingite, a complex calcium aluminate cement hydrate (C2 ASH8) that gives modern cements good durability and compressive strength. Specific gravity tests and a new petrographic method for assessing bulk densities indicate unit weights of about 1750 kg/m3 for the wall mortars and 1430–1640 kg/m3 for the pumice bearing, vaulted ceiling mortars. Innovative point load source tests record the tensile strengths (ft) of the aggregate and interfacial elements of the conglomeratic concrete fabric. These suggest ft of about 2.7 MPa for brick, 1.2 MPa for Tufo Lionato tuff, and 0.9 MPa for Tufo Giallo della Via Tiberina tuff coarse aggregate (caementa), based on a tentative, approximate correlation with splitting (Brazilian) tests. The pozzolanic mortar and interfacial zones have lower ft in the range of 0.8 MPa to 0.5 MPa. The relatively low mortar strength and its somewhat tenuous adhesion to the coarse aggregate suggests that the caementa may have arrested the propagation of tensile microcracks that formed in the mortar, thereby increasing the composite tensile strength of the concrete. Roman builders selected the complex aggregate mixes to optimize the performance of the wall and vault concretes.  相似文献   

12.
The functional morphology of postcranial remains can be used to infer habitat preference. This approach is typically considered an “ecomorphological” method, and has frequently been applied to bovid postcranial remains. Methods for predicting habitat preference from bovid postcrania currently exist for femora, metapodials, and astragali. Here we describe three methods for predicting paleohabitats using measurements of African bovid phalanges (proximal, intermediate, and distal). The proximal phalanx method correctly predicted the habitat preference for 130 of 183 modern bovid specimens (71.0%, 2.8 times better than chance, p < 0.0001). The intermediate phalanx method correctly predicted the habitat preference for 115 of 163 modern bovid specimens (70.6%, 2.8 times better than chance, p < 0.0001). The distal phalanx method correctly predicted the habitat preference for 87 of 122 modern bovid specimens (71.3%, 2.8 times better than chance, p < 0.0001). These accuracies compare well with those of existing such methods (1.8–3.4 times better than chance). Analysis of the probabilities associated with the habitat predictions allows confidence thresholds to be established that identify specific predictions which have <5% chance of being in error. This raises the effective accuracy of the methods to 95%. Extensive exploration and manipulation of the underlying data demonstrate that the habitat predictions are generally robust, and are relatively independent of body weight, taxonomy, and sample composition. These methods are broadly applicable, relatively accurate, and can be used to generate independent predictions of habitat from different elements, and thus constitute a useful approach to inferring past environments.  相似文献   

13.
Archaeologists have long recognized the problem of the “old wood” effect in radiocarbon dating charcoal and wood samples, the age of which may be hundreds of years older than their use by humans. Such problems have resulted in significant changes in how most researchers select wood and charcoal samples for 14C dating, with many now using relatively short-lived carbonized materials for dating. Despite the significant strides made in our understanding of the potential biases of the “old wood” effect, little emphasis has been placed on the possible impacts of dating “old shell” in archaeological deposits. The use of marine shell for 14C dating is widespread in coastal areas around the world, including a growing emphasis on the dating of individual shell artifacts via Accelerator Mass Spectrometry (AMS). In dating shell artifacts, we have obtained several dates older than associated 14C dates for short-lived subsistence remains from the same deposits, including great disparities (>10,000 years) and more subtle differences (≥100 years). These discrepancies appear to be due to the use of old shells by humans to make beads and other artifacts, including shells collected from fossil deposits, older archaeological sites, and beaches. The problems caused by the use of old shells to make beads and other artifacts are surmountable through careful sample selection, analysis of multiple 14C dates on a variety of materials, and proper calibration procedures.  相似文献   

14.
Snake Cave (Thailand) is an important site for the study of the evolution in Southeast Asia, leading to a discovery of rich and various faunas, including a human tooth. Fossils of large and small mammals converge to indicate, on the basis of faunal assemblage, a late Middle Pleistocene age for the fossiliferous layers; on the other hand, previous U-series dating of carbonates furnished a lower limit for the fossils of about 130 ky.In order to achieve a better comprehension of the chronology of the cave, the Uranium-series method for absolute age determination has been applied to some carbonates older than those studied previously and to fossils themselves.We used the isochron technique approach to yield valuable ages because spleleothem samples consist in a mixture of calcite and detrital contamination. The results obtained suggest that the main fossiliferous level is older than about 160 ky. The application of the U-series method to tooth samples from this tropical cave leads to erroneous ages, probably because of post depositional groundwater movements.  相似文献   

15.
A data set of 87 radiocarbon determinations obtained for the Bronze Age Khuzhir-Nuge XIV cemetery in the Cis-Baikal region of Siberia is analyzed from the perspective of data quality and within the local archaeological context. Bone preservation, expressed in terms of collagen yields, is a very important factor affecting both the accuracy and precision of 14C dates and, therefore, publication of this information should be adopted as a required standard. According to the calibrated high-collagen dates, after a single Serovo interment the cemetery was used continuously by Glazkovo peoples for up to 700 years (∼2700–2000 BC), and 70% of all burials were interred within a relatively short peak period between approximately 2500 and 2300 BC. The extensive radiocarbon data from KN XIV allow for the re-evaluation of existing models and perspectives on the place of the Glazkovo culture within the Cis-Baikal Neolithic and Bronze Age.  相似文献   

16.
We have explored laser depth profiling to obtain data sets for U-series as well as Sr analyses. Laser probing with an 81 μm spot size allows for the exploration of low uranium domains of up to 400 μm below the outer surface in tooth enamel. These low U domains will contain Sr isotope compositions of the individual, that are least affected by diagenetic Sr overprints. The small holes drilled for U surveying are not visible to the naked eye. Using larger spot sizes of around 233 μm, laser drilling can be used to obtain reliable U-series isotope data to a depth of approximately 1000 μm in enamel and around 1300 μm in bone. Furthermore, meaningful 87Sr/86Sr isotope data can also be obtained with this spot size. Using our sampling strategy, the overall damage to a human tooth is minute, as demonstrated on a Neanderthal tooth from Moula-Guercy. We expect that laser ablation depth profiling will become routine for gaining insights into the age of human fossils and the migrations of ancient humans.  相似文献   

17.
Pine marten, Martes martes, is the dominating fur prey at three contemporaneous Danish Late Atlantic sites, Agernæs (EMNI = 34), Ringkloster (EMNI = 41) and Tybrind Vig (EMNI = 26). All skeletal elements are represented and the only marks present on the skeleton are those consistent with skinning. Burned teeth in the three populations suggest either new hunting methods or a ritual act. Ringkloster is on the mainland, while Tybrind Vig and Agernæs are island localities. Morphometric data indicate that the subfossil population of larger individuals was maintained on the mainland due to free migration, while the animals in the subfossil island populations had decreased in size in the Late Atlantic.  相似文献   

18.
Eleven Olivella biplicata spire-lopped shell beads from six sites located 250–365 km inland from the Pacific coast of southern California produced AMS dates between 11,200 and 7860 CAL BP. Olivella shell beads were well-documented items of prestige and media of exchange in Native California, and recovery of these examples from inland contexts indicates low-level exchange between resident populations of the coast and the southwestern Great Basin by at least 10,300–10,000 CAL years BP. These findings represent some of the earliest unequivocal evidence for long-distance trade in western North America and push the antiquity of this important form of inter-group interaction back several thousand years earlier than previously thought.  相似文献   

19.
Recent excavations at the Neolithic site of Hagoshrim, northern Israel, have yielded a large assemblage of skeletal fragments, representing mostly caprines, cattle and pigs. The three layers of the site's occupation span approximately 2000 years of a crucial period in the domestication of these taxa in the southern Levant, including Pre-Pottery Neolithic C (Layer 6, 7562 ± 85 BP and 7735 ± 55 BP) and the Pottery Neolithic cultures, Jericho IX (Layer 5, 6725 ± 120 BP) and Wadi Raba (Layer 4, 6505 ± 120 BP). Therefore, this site provides an outstanding opportunity to study the process of domestication in a comparative manner, both across taxa and through time. We used kill-off patterns, size reduction and changes in body proportions, and introduced statistical methods to discern the different stages of the domestication process for each taxon. Pig remains reflect simultaneous changes at the end of the 7th millennium BP: kill-off patterns, size and proportions of cranial and post-cranial elements all change between Layer 5 and 4 with no significant changes between Layer 6 and 5. Gradual changes—both between Layer 6 and 5 and between Layer 5 and 4—were found only for cattle, while caprine remains exhibit no changes throughout the site's occupation. These results can be explained in light of the differences between the taxa in terms of their life history strategies, among other things, that can be viewed as pre-adaptations to domestication.  相似文献   

20.
Instrumental neutron activation analysis was performed on 79 obsidian tools and flakes from 35 sites on Sakhalin Island dating from Upper Paleolithic (c. 19,000 bp ) to Early Iron Age (c. 2000–800 bp ). Due to the absence of volcanic glass on Sakhalin Island, raw materials from the nearest obsidian sources on Hokkaido Island, such as Oketo, Shirataki, Tokachi-Mitsumata, and Akaigawa, were also analysed. A strong correlation between the chemical compositions of obsidian artefacts from Sakhalin and volcanic glass sources from Hokkaido was discovered. In particular, the Oketo and Shirataki sources were used for tool manufacturing throughout all of Sakhalin Island's prehistory. The distances between sources and archaeological sites range from 200–1000 km. The intensive exchange of raw materials continued and even intensified after the appearance of the La Pérouse (Soya) Strait between Hokkaido and Sakhalin about 10,000–8000 bp. The Sakhalin Island populations were deeply involved in the obsidian exchange network centered on Hokkaido.  相似文献   

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