337 research outputs found

    Interpretation and significance of urban deposits

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    In many United Kingdom cities, the late Roman to Medieval periods are an archaeological blank. The study of contemporary anthropogenic deposits is therefore crucial to any understanding of urban activity. Using pedological and micromorphological techniques, urban anthropogenic deposits of this age from London and Exeter were therefore investigated. lt can be suggested from the results that previous interpretations of such deposits, once thought of as »flood loams» and often termed »Dark Earth », as i progressively thickening within-urban area »market garden» soils, orii simple accumulations of urban dump material through time, are inadequate. Analysis of undisturbed soil samples through optical microscopy, complemented by archaeological information from individual sites, allow us to be more specific. Our observations may indicate phases of dumping of mainly local soil material from, for example, military ditch digging at Exeter; whereas, at the London sites the deposits are tentatively interpreted as accumulations of partially or fully reworked materials derived from the destruction and collapse of insubstantial buildings. This finding may infer a gross under-estimation of urban activity at this time. Micromorphology has proven tobe the best analytical technique. In contrast, analyses of bulk samples may only provide very general information in these often extremely heterogeneous deposits

    Prisoner's Dilemma cellular automata revisited: evolution of cooperation under environmental pressure

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    We propose an extension of the evolutionary Prisoner's Dilemma cellular automata, introduced by Nowak and May \cite{nm92}, in which the pressure of the environment is taken into account. This is implemented by requiring that individuals need to collect a minimum score UminU_{min}, representing indispensable resources (nutrients, energy, money, etc.) to prosper in this environment. So the agents, instead of evolving just by adopting the behaviour of the most successful neighbour (who got UmsnU^{msn}), also take into account if UmsnU^{msn} is above or below the threshold UminU_{min}. If Umsn<UminU^{msn}<U_{min} an individual has a probability of adopting the opposite behaviour from the one used by its most successful neighbour. This modification allows the evolution of cooperation for payoffs for which defection was the rule (as it happens, for example, when the sucker's payoff is much worse than the punishment for mutual defection). We also analyse a more sophisticated version of this model in which the selective rule is supplemented with a "win-stay, lose-shift" criterion. The cluster structure is analyzed and, for this more complex version we found power-law scaling for a restricted region in the parameter space.Comment: 15 pages, 8 figures; added figures and revised tex

    Conceptualising examinable physical education in the Irish context: Leaving Certificate Physical Education

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    peer-reviewedA Physical Education Development Group (PEDG) was responsible for constructing a new school subject curriculum, Leaving Certificate Physical Education (LCPE), in Ireland. This paper provides an insight into this development group and explores the process of curriculum development, and the influence of roles and power-ratios within the group, in the construction of the LCPE curriculum. Figurational sociology concepts (Elias, 1978) were drawn on to make sense of the curriculum makers’ experiences. Interviews were conducted with 10 PEDG members. The findings suggest that the members’ roles had very little, if any, influence on the curriculum development process. Findings also revolved around the unbalanced power-ratios which existed in the PEDG and highlighted the socially powerful position of ‘strong, well-established’ (in the academic field of curriculum development – participant's words) members and the other members (predominantly representing practicing teachers). We express concern for the role of teachers in the curriculum process and argue that they play a crucial and significant role in the school subject curriculum development process. This paper supports Goodson’s (1983) and Penney’s (2006) conceptualisation of the contested and socially constructed nature of the curriculum development process.peer-reviewe

    The contexts and early Acheulean archaeology of the EF-HR paleo-landscape (Olduvai Gorge, Tanzania)

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    Renewed fieldwork at the early Acheulean site of EF-HR (Olduvai Gorge, Tanzania) has included detailed stratigraphic studies of the sequence, extended excavations in the main site, and has placed eleven additional trenches within an area of nearly 1 km(2), to sample the same stratigraphic interval as in the main trench across the broader paleo-landscape. Our new stratigraphic work suggests that EF-HR is positioned higher in the Bed II sequence than previously proposed, which has implications for the age of the site and its stratigraphic correlation to other Olduvai Middle Bed II sites. Geological research shows that the main EF-HR site was situated at the deepest part of an incised valley formed through river erosion. Archaeological excavations at the main site and nearby trenches have unearthed a large new assemblage, with more than 3000 fossils and artefacts, including a hundred handaxes in stratigraphic position. In addition, our test-trenching approach has detected conspicuous differences in the density of artefacts across the landscape, with a large cluster of archaeological material in and around the main trench, and less intense human activity at the same level in the more distant satellite trenches. All of these aspects are discussed in this paper in the light of site formation processes, behavioral contexts, and their implications for our understanding of the early Acheulean at Olduvai Gorge

    How old is the Tasmanian cultural landscape? a test of landscape openness using quantitative land-cover reconstructions

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    Aim: To test competing hypotheses about the timing and extent of Holocene landscape opening using pollen-based quantitative land-cover estimates. Location: Dove Lake, Tasmanian Wilderness World Heritage Area, Australia. Methods: Fossil pollen data were incorporated into pollen dispersal models and corrected for differences in pollen productivity among key plant taxa. Mechanistic models (REVEALS-Regional Estimates of VEgetation Abundance from Large Sites) employing different models for pollen dispersal (Gaussian plume and Lagrangian stochastic models) were evaluated and applied in the Southern Hemisphere for the first time. Results: Validation of the REVEALS model with vegetation cover data suggests an overall better performance of the Lagrangian stochastic model. Regional land-cover estimates for forest and non-forest plant taxa show persistent landscape openness throughout the Holocene (average landscape openness similar to 50%). Gymnoschoenus sphaerocephalus, an indicator of moorland vegetation, shows higher values during the early Holocene (11.7-9 ka) and declines slightly through the mid-Holocene (9-4.5 ka) during a phase of partial landscape afforestation. Rain forest cover reduced (from similar to 40% to similar to 20%) during the period between 4.2-3.5 ka. Main conclusions: Pollen percentages severely under-represent landscape openness in western Tasmania and this bias has fostered an over-estimation of Holocene forest cover from pollen data. Treeless vegetation dominated Holocene landscapes of the Dove Lake area, allowing us to reject models of landscape evolution that invoke late-Holocene replacement of a rain forest-dominated landscape by moorland. Instead, we confirm a model of Late Pleistocene inheritance of open vegetation. Rapid forest decline occurred after c.4 ka, likely in response to regional moisture decline.Australian Research Council; AINSE AWARD [ALNGRA16024]; AINSE PGRA scholarship [12039]info:eu-repo/semantics/publishedVersio

    New excavations at the HWK EE site: Archaeology, paleoenvironment and site formation processes during late Oldowan times at Olduvai Gorge, Tanzania

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    This paper reports the results of renewed fieldwork at the HWK EE site (Olduvai Gorge, Tanzania). HWK EE is positioned across the boundary between Lower and Middle Bed II, a crucial interval for studying the emergence of the Acheulean at Olduvai Gorge. Our excavations at HWK EE have produced one of the largest collections of fossils and artefacts from any Oldowan site, distributed across several archaeological units and a large excavation surface in four separate trenches that can be stratigraphically correlated. Here we present the main stratigraphic and archaeological units and discuss site formation processes. Results show a great density of fossils and stone tools vertically through two stratigraphic intervals (Lemuta and Lower Augitic Sandstone) and laterally across an area of around 300 m2, and highlight the confluence of biotic and abiotic agents in the formation of the assemblage. The large size and diversity of the assemblage, as well as its good preservation, qualify HWK EE as a reference site for the study of the late Oldowan at Olduvai Gorge and elsewhere in Africa. In addition, the description of the stratigraphic and archaeological sequence of HWK EE presented in this paper constitutes the foundation for further studies on hominin behavior and paleoecology in Lower and Middle Bed II

    Mid‐Holocene site formation, diagenesis and human activity at the foothills of Serra da Estrela (Portugal)

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    UIDB/00749/2020 UIDP/00749/2020The Neolithic occupation of Penedo dos Mouros in the foothills of Serra da Estrela, PortugalÊŒs highest mountain, dates to the 5th to 4th millennia cal B.C. The siteÊŒs faunal assemblage is extremely rare in the regional prehistoric archaeological record, due to the acidity of the granitic geology. This underlines Penedo dos Mouros importance as a reference site for understanding early pastoralism in the region. Due to the insufficient survival of bone collagen for radiocarbon dating and the homogeneity of the stratigraphy, where most visible contacts are due to postdepositional processes, we chose micromorphology to address the reasons behind the bone preservation and to assess the stratigraphic integrity of the prehistoric deposit. Reworking of eroding saprolitic soils was a major factor in the sediment accumulation, with remains of short human occupation events. Possible evidence for clearance fires linked to the first occurrences of pastoralism practised in the region, creating open spaces for grazing, was identified. Post‐depositional carbonate cementation derived from ashes, identifiable at the microscopic scale, enabled bone preservation. Carbonate and spodic‐like features document water saturation once the sedimentation ceased. This sedimentary dynamic has broader geomorphological implications, such as an inferred post‐Neolithic incision of the stream valley adjacent to the site.publishersversionpublishe
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