153 resultados para Late Dorset


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Changes in the geological interpretation of the history of the ancient Solent river basin have focused attention on the handaxes discovered in the Corfe Mullen area during quarrying before the Second World War. Recent geological research suggests that the fluvial terrace the handaxes are associated with may pre-date the Anglian glaciation. This is important because it contributes to the question of just when the Solent basin was first occupied by hominins, and how this relates to other areas of possible contemporary pre-Anglian occupation such as the Boxgrove Marine embayment. However, the artefacts were believed to come from the bluff of the river terrace and were thus not in situ. This paper explores that question and re-examines the context from which the handaxes at Corfe Mullen were discovered.

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Carbon and nitrogen stable isotope ratios of 45 human and 23 faunal bone collagen samples were measured to study human diet and the management of domestic herbivores in past Jordan, contrasting skeletal remains from the Middle and Late Bronze Age and the Late Roman and Byzantine periods from the site of Ya'amūn near Irbid. The isotope data demonstrate that the management of the sheep and goats changed over time, with the earlier animals consuming more plants from semi-arid habitats, possibly because of transhumant herding strategies. The isotope data for fish presented here are the first from archaeological contexts from the Southern Levant. Although fish of diverse provenance was available at the site, human diet was predominately based on terrestrial resources and there was little dietary variability within each time-period. Isotopic variation between humans from different time-periods can mostly be explained by ‘baseline shifts’ in the available food sources; however, it is suggested that legumes may have played a more significant role in Middle and Late Bronze Age diet than later on.

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A Hale cycle, one complete magnetic cycle of the Sun, spans two complete Schwabe cycles (also referred to as sunspot and, more generally, solar cycles). The approximately 22-year Hale cycle is seen in magnetic polarities of both sunspots and polar fields, as well as in the intensity of galactic cosmic rays reaching Earth, with odd- and even-numbered solar cycles displaying qualitatively different waveforms. Correct numbering of solar cycles also underpins empirical cycle-to-cycle relations which are used as first-order tests of stellar dynamo models. There has been much debate about whether the unusually long solar cycle 4 (SC4), spanning- 1784–1799, was actually two shorter solar cycles combined as a result of poor data coverage in the original Wolf sunspot number record. Indeed, the group sunspot number does show a small increase around 1794–1799 and there is evidence of an increase in the mean latitude of sunspots at this time, suggesting the existence of a cycle ‘‘4b’’. In this study, we use cosmogenic radionuclide data and associated reconstructions of the heliospheric magnetic field (HMF) to show that the Hale cycle has persisted over the last 300 years and that data prior to 1800 are more consistent with cycle 4 being a single long cycle (the ‘‘no SC4b’’ scenario). We also investigate the effect of cycle 4b on the HMF using an open solar flux (OSF) continuity model, in which the OSF source term is related to sunspot number and the OSF loss term is determined by the heliospheric current sheet tilt, assumed to be a simple function of solar cycle phase. The results are surprising; Without SC4b, the HMF shows two distinct peaks in the 1784–1799 interval, while the addition of SC4b removes the secondary peak, as the OSF loss term acts in opposition to the later rise in sunspot number. The timing and magnitude of the main SC4 HMF peak is also significantly changed by the addition of SC4b. These results are compared with the cosmogenic isotope reconstructions of HMF and historical aurora records. These data marginally favour the existence of SC4b (the ‘‘SC4b’’ scenario), though the result is less certain than that based on the persistence of the Hale cycle. Thus while the current uncertainties in the observations preclude any definitive conclusions, the data favour the ‘‘no SC4b’’ scenario. Future improvements to cosmogenic isotope reconstructions of the HMF, through either improved modelling or additional ice cores from well-separated geographic locations, may enable questions of the existence of SC4b and the phase of Hale cycle prior to the Maunder minimum to be settled conclusively.

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Our understanding of the introduction and adoption of new plant foods in Roman Britain is currently limited by a lack of data from a group of Late Iron Age settlements commonly referred to as oppida (large pre-Roman towns). This paper presents the first evidence of several imported plant foods from Late Iron Age Britain in the form of waterlogged plant remains from the oppidum at Silchester. These were recovered from the basal contexts of two wells, dated to the early first century a.d. One olive stone and several seeds of celery, coriander and dill were identified. The results are compared to archaeobotanical data from elsewhere in Britain and northwestern Europe, demonstrating that Silchester is part of the wider phenomenon of the adoption of new flavourings and fruits in Late Iron Age Europe.

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The paper begins by considering the importance of springs as a focus for votive deposits in Bronze Age Britain. This is not a new idea, but nowhere has this association been examined through the excavation of one of these features. The point is illustrated by excavation at the findspot of a famous group of Late Bronze Age weapons, the Broadward hoard, discovered in 1867. Little was known about the site, where it was found or the character of the original deposit, but a study of contemporary accounts of the hoard, combined with geophysical and topographical surveys, led to small-scale excavation in 2010, which showed that the deposit had most probably been buried in a pit on the edge of a spring. Other finds associated with the spring included an Early Bronze Age macehead, a Roman pot and various Saxon and medieval animal bones. The latest deposit, with a post-medieval carbon date, included a wooden knife or dagger. An adjacent palaeochannel provided an important environmental sequence for this part of the English–Welsh borderland and suggests that the Late Bronze Age hoard had been deposited not far from a settlement. A nearby earthwork enclosure was associated with a clay weight, which may be of similar date. Despite the limited scale of the fieldwork, it illustrates the potential for treating springs associated with artefact finds on the same terms as other archaeological deposits.

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The papers in this volume were presented at a Mellon-Sawyer Seminar held at the University of Oxford in 2009-2010, which sought to investigate side by side the two important movements of conversion that frame late antiquity: to Christianity at its start, and to Islam at the other end. Challenging the opposition between the two stereotypes of Islamic conversion as an intrinsically violent process, and Christian conversion as a fundamentally spiritual one, the papers seek to isolate the behaviours and circumstances that made conversion both such a common and such a contested phenomenon. The spread of Buddhism in Asia in broadly the same period serves as an external comparator that was not caught in the net of the Abrahamic religions. The volume is organised around several themes, reflecting the concerns of the initial project with the articulation between norm and practice, the role of authorities and institutions, and the social and individual fluidity on the ground. Debates, discussions, and the expression of norms and principles about conversion conversion are not rare in societies experiencing religious change, and the first section of the book examines some of the main issues brought up by surviving sources. This is followed by three sections examining different aspects of how those principles were - or were not - put into practice: how conversion was handled by the state, how it was continuously redefined by individual ambivalence and cultural fluidity, and how it was enshrined through different forms of institutionalization. Finally, a topographical coda examines the effects of religious change on the iconic holy city of Jerusalem.

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An enhanced radiocarbon-dated pollen-stratigraphical record from Rovegno (Liguria, 812m asl), northern Apennines (Italy), has provided a history of vegetation succession from before 17,056-16,621 cal yrs BP to the present day. The record indicates the transition from open Pinus woodland to Artemisia dominated grassland, and finally Juniperus shrubland during the late Würm. This is succeeded by Betula and Pinus woodland, and the expansion of thermophilous taxa, namely Abies, Corylus and Quercus during the Late Würm Lateglacial Interstadial. The ‘Younger Dryas’ is possibly represented by an increase in Betula and Artemisia. During the early Holocene, mixed coniferous-deciduous woodland is dominant with Quercus, as well as Abies, Fagus and Corylus. Fagus woodland becomes established sometime before 6488-6318 cal yrs BP, but never becomes a major component of the woodland cover. Throughout the middle Holocene, Abies woodland fl uctuates, with marked declines between 6488-6318 cal yrs BP and 5287-4835 cal yrs BP, although the cause remains uncertain. Finally, the paper evaluates the application of non-pollen palynomorphs, especially coprophilous fungal spores, at Prato Spilla ‘A’ (Emilia Romagna) and concludes that greater caution must be used when interpreting middle Holocene human activity based upon pollen data alone

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This paper presents evidence of the discovery of a new Middle Pleistocene site in central southern England, with undisturbed evidence of hominin occupation well-dated to an interstadial towards the end of Marine Isotope Stage 8, c. 250,000 BP. The site consists of a preserved remnant of a river terrace and its alluvial floodplain overlain by chalk-rich bankside deposits, all abutting a Chalk bedrock riverbank. It preserves an area of occupation with activity focused on the riverbank, complemented by occasional activity on a palaeo-landsurface developed on the surface of the alluvial floodplain. Lithic technology at the site consists almost entirely of handaxe manufacture, allowing attribution to an Acheulian industrial tradition. Mammalian and other palaeo-environmental remains are present and associated with the occupation horizons, including large mammal bones showing signs of hominin interference. Dating was based on OSL determinations on the sediments and amino acid racemisation of molluscan remains, supported by biostratigraphic indications. Besides being a rare instance of an undisturbed Palaeolithic palaeo-landscape covering several hectares, the site contributes to wider Quaternary research concerns over the ability of Middle Pleistocene hominins to tolerate colder climatic episodes in higher latitudes, and over settlement history and changing lithic industrial traditions of northwest Europe in relation to climate change and British peninsularity. It is suggested that the Harnham evidence may represent an insular population that had persisted in southern Britain since MIS 10/9, which became locally extinct during the glacial maximum 8.2 marking the end of MIS 8.

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This paper examines two late medieval abridgements of Gerald of Wales’ Expugnatio Hibernica, one in Hiberno-English and one in Irish. The manuscripts in which these adaptations survive all date from the late fifteenth century and appear to bear witness to a sudden and pronounced interest in Gerald’s text. Drawing on evidence from the extant manuscripts, this paper explores the readerships of, and the nature of their interest in, these adaptations. A key conclusion is that the Expugnatio, which gives prominence to Gerald's own relatives, the Fitzgeralds, was valued as a family history by the Fitzgerald Earls of Kildare and their allies. The Earls were at the height of their power in the period in which these manuscripts were produced. Examination of this neglected evidence of the adaptation and readership of the Expugnatio in late medieval Ireland suggests that, for some medieval readers at least, the primary identities Gerald’s text expressed were familial and local rather than colonial or national.

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Identifying predictability and the corresponding sources for the western North Pacific (WNP) summer climate in the case of non-stationary teleconnections during recent decades benefits for further improvements of long-range prediction on the WNP and East Asian summers. In the past few decades, pronounced increases on the summer sea surface temperature (SST) and associated interannual variability are observed over the tropical Indian Ocean and eastern Pacific around the late 1970s and over the Maritime Continent and western–central Pacific around the early 1990s. These increases are associated with significant enhancements of the interannual variability for the lower-tropospheric wind over the WNP. In this study, we further assess interdecadal changes on the seasonal prediction of the WNP summer anomalies, using May-start retrospective forecasts from the ENSEMBLES multi-model project in the period 1960–2005. It is found that prediction of the WNP summer anomalies exhibits an interdecadal shift with higher prediction skills since the late 1970s, particularly after the early 1990s. Improvements of the prediction skills for SSTs after the late 1970s are mainly found around tropical Indian Ocean and the WNP. The better prediction of the WNP after the late 1970s may arise mainly from the improvement of the SST prediction around the tropical eastern Indian Ocean. The close teleconnections between the tropical eastern Indian Ocean and WNP summer variability work both in the model predictions and observations. After the early 1990s, on the other hand, the improvements are detected mainly around the South China Sea and Philippines for the lower-tropospheric zonal wind and precipitation anomalies, associating with a better description of the SST anomalies around the Maritime Continent. A dipole SST pattern over the Maritime Continent and the central equatorial Pacific Ocean is closely related to the WNP summer anomalies after the early 1990s. This teleconnection mode is quite predictable, which is realistically reproduced by the models, presenting more predictable signals to the WNP summer climate after the early 1990s.

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Children represent the most vulnerable members of society, and as such provide valuable insight into past lifeways. Adverse environmental conditions translate more readily into the osteological record of children, making them primary evidence for the investigation of ill-health in the past. To date, most information on growing up in Roman Britain has been based on the Classical literature, or discussed in palaeopathological studies with a regional focus, e.g. Dorset or Durnovaria. Thus, the lifestyles and everyday realities of children throughout Britannia remained largely unknown. This study sets out to fill this gap by providing the first large scale analysis of Romano-British children from town and country. The palaeopathological analysis of 1643 non-adult (0-17 years) skeletons, compiled from the literature (N=690) and primary osteological analysis (N=953), from 27 urban and rural settlements has highlighted diverse patterns in non-adult mortality and morbidity. The distribution of ages-at-death suggest that older children and adolescents migrated from country to town, possibly for commencing their working lives. True prevalence rates suggest that caries (1.8%) and enamel hypoplasia (11.4%) were more common in children from major urban towns, whereas children in the countryside displayed higher frequencies of scurvy (6.9%), cribra orbitalia (27.7%), porotic hyperostosis (6.2%) and endocranial lesions (10.9%). Social inequality in late Roman Britain may have been the driving force behind these urban-rural dichotomies. The results may point to exploitation of the peasantry on the one hand, and higher status of the urban population as a more ‘Romanised’ group on the other. Comparison with Iron Age and post-medieval non-adults also demonstrated a decline in health in the Roman period, with some levels of ill-health, particularly in the rural children, similar to those from post-medieval London. This research provides the most comprehensive study of non-adult morbidity and mortality in Roman Britain to date. It has provided new insights into Romano-British lifeways and presents suggestions for further work.

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Stable isotope analysis of leaf waxes in a sediment core from Laguna La Gaiba, a shallow lake located at the Bolivian margin of the Pantanal wetlands, provides new perspective on vegetation and climate change in the lowland interior tropics of South America over the past 40,000 years. The carbon isotopic compositions (δ13C) of long-chain n-alkanes reveal large shifts between C3-and C4-dominated vegetation communities since the last glacial period, consistent with landscape reconstructions generated with pollen data from the same sediment core. Leaf wax δ13C values during the last glacial period reflect an open landscape composed of C4grasses and C3herbs from 41–20ka. A peak in C4abundance during the Last Glacial Maximum (LGM, ∼21ka) suggests drier or more seasonal conditions relative to the earlier glacial period, while the development of a C3-dominated forest community after 20 ka points to increased humidity during the last deglaciation. Within the Holocene, large changes in the abundance of C4 vegetation indicate a transition from drier or more seasonal conditions during the early/mid-Holocene to wetter conditions in the late Holocene coincident with increasing austral summer insolation. Strong negative correlations between leaf wax δ13C and δD values over the entire record indicate that the majority of variability in leaf wax δD at this site can be explained by variability in the magnitude of biosynthetic fractionation by different vegetation types rather than changes in meteoric water δD signatures. However, positive δD deviations from the observed δ13C–δD trends are consistent with more enriched source water and drier or more seasonal conditions during the early/mid-Holocene and LGM. Overall, our record adds to evidence of varying influence of glacial boundary conditions and orbital forcing on South American Summer Monsoon precipitation in different regions of the South American tropics. Moreover, the relationships between leaf wax stable isotopes and pollen data observed at this site underscore the complementary nature of pollen and leaf wax δ13C data for reconstructing past vegetation changes and the potentially large effects of such changes on leaf wax δD signatures.

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Reconstructions of salinity are used to diagnose changes in the hydrological cycle and ocean circulation. A widely used method of determining past salinity uses oxygen isotope (δOw) residuals after the extraction of the global ice volume and temperature components. This method relies on a constant relationship between δOw and salinity throughout time. Here we use the isotope-enabled fully coupled General Circulation Model (GCM) HadCM3 to test the application of spatially and time-independent relationships in the reconstruction of past ocean salinity. Simulations of the Late Holocene (LH), Last Glacial Maximum (LGM), and Last Interglacial (LIG) climates are performed and benchmarked against existing compilations of stable oxygen isotopes in carbonates (δOc), which primarily reflect δOw and temperature. We find that HadCM3 produces an accurate representation of the surface ocean δOc distribution for the LH and LGM. Our simulations show considerable variability in spatial and temporal δOw-salinity relationships. Spatial gradients are generally shallower but within ∼50% of the actual simulated LH to LGM and LH to LIG temporal gradients and temporal gradients calculated from multi-decadal variability are generally shallower than both spatial and actual simulated gradients. The largest sources of uncertainty in salinity reconstructions are found to be caused by changes in regional freshwater budgets, ocean circulation, and sea ice regimes. These can cause errors in salinity estimates exceeding 4 psu. Our results suggest that paleosalinity reconstructions in the South Atlantic, Indian and Tropical Pacific Oceans should be most robust, since these regions exhibit relatively constant δOw-salinity relationships across spatial and temporal scales. Largest uncertainties will affect North Atlantic and high latitude paleosalinity reconstructions. Finally, the results show that it is difficult to generate reliable salinity estimates for regions of dynamic oceanography, such as the North Atlantic, without additional constraints.