61 resultados para Human ecology - History

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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Classical or transferase-deficient galactosaemia is an inherited metabolic disorder caused by mutation in the human Galactose-1-phosphate uridyl transferase (GALT) gene. Of some 170 causative mutations reported, fewer than 10% are observed in more than one geographic region or ethnic group. To better understand the population history of the common GALT mutations, we have established a haplotyping system for the GALT locus incorporating eight single nucleotide polymorphisms and three short tandem repeat markers. We analysed haplotypes associated with the three most frequent GALT gene mutations, Q188R, K285N and Duarte-2 (D2), and estimated their age. Haplotype diversity, in conjunction with measures of genetic diversity and of linkage disequilibrium, indicated that Q188R and K285N are European mutations. The Q188R mutation arose in central Europe within the last 20 000 years, with its observed east-west cline of increasing relative allele frequency possibly being due to population expansion during the re-colonization of Europe by Homo sapiens in the Mesolithic age. K285N was found to be a younger mutation that originated in Eastern Europe and is probably more geographically restricted as it arose after all major European population expansions. The D2 variant was found to be an ancient mutation that originated before the expansion of Homo sapiens out of Africa. Heredity (2010) 104, 148-154; doi:10.1038/hdy.2009.84; published online 29 July 2009

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This review article considers Samuel Moyn’s book The Last Utopia:Human Rights in History in the context of recent trends in the writing of human rights history. A central debate among historians of human rights, in seekingto account for the genesis and spread of human rights, is how far current humanrights practice demonstrates continuity or radical discontinuity with previousattempts to secure rights. Moyn’s discontinuity thesis and the controversysurrounding it exemplify this debate. Whether Moyn is correct is importantbeyond the confines of human rights historiography, with implications for theirmeaning in law, as well as their political legitimacy. This review argues that Moyn’s book ultimately fails to convince, for two broad reasons. First, a more balanced judgment would conclude that the history of human rights is both one of continuity and discontinuity. Second, and more importantly, Moyn fails to offer a convincing account of the normativity of human rights. Undertaking a history of human rights requires a deeper engagement with debates on the nature and validity of human rights than Moyn seems prepared to contemplate.

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This paper first explores the conflictual discourses employed by government agencies, citizens’ initiatives, and environmental organizations over the construction of a High Voltage Power Station (KYT) for demands of the 2004 Olympic Games, as presented in media reports and movement literature over a period of one year. Having in mind recent criticisms targeting the lack of empirical evidence in Ulrich Beck’s risk theorization, this exploration is of distinct importance. Secondly, it takes into account that both the defensive character of societal action and mistrust to expert authorities have been confirmed as prevalent characteristics of both the Greek and the general risk social context. The paper attempts to re-evaluate and/or complement existing perspectives of societal activism in general and environmental mobilizations in particular within the confines of the Greek social context. As a tentative conclusion, it is suggested that the risk perspective offers a novel prism for the examination of societal activism without confining it to the characteristics of individual national contexts.

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Holocene climates and human impact in the Mediterranean basin have received much attention, but the Maltese Islands in the Central Mediterranean, although a pivotal area, have been little researched. Here, sedimentary and palynological data are presented for three cores from the Holocene coastal and shallowmarine
deposits of the Maltese Islands. These show deforestation from Pinus-Cupressaceae woodland in the early Neolithic, and then a long, but relatively stable history of agriculturally degraded environments to the present day. The major climate events which have affected the Italian and Balkan peninsulas to the
north, and Tunisia to the south, are not reflected in the pollen diagrams from the Maltese Islands because of the strong anthropogenic imprint on the Maltese vegetation from early in the Neolithic. Previous suggestions of environmentally-driven agricultural collapse at the end of the Neolithic appear, however,
to be substantiated and may be linked to regional aridification around 4300 cal. BP. Depopulation in early Medieval times is not supported by the current palynological evidence.

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This paper presents findings based on a palynological investigation of artificially accreting (plaggen) soils from the settlement of Village Bay, Hirta, in the St Kilda archipelago, which was perhaps the most distant and inhospitable outpost of sustained human habitation in the British Isles. The soils were developed principally through the addition of turf ash and seabird waste, although some ash may have been derived from upland peats. It is assumed that the woodland pollen signal (much lower in the soils than in an upland peat site nearby) represents off-island sources. Corylus avellana-type pollen (frequent in upland sites), along with Potentilla-type, may provide markers in the Village Bay profiles for the addition of ashed hillside turf, and possibly peat, to the plaggen soils. Cereal-type pollen is well represented through the profiles and is often strongly associated with the record for Chrysanthemum segetum (corn marigold), a frequent indicator of arable land. The Brassicaceae signal may partly reflect the cultivation of cabbages; Chelidonium majus (greater celandine) may have been grown for medicinal use. Soil mixing has rendered radiocarbon dating meaningless at this site, but the establishment of a change in cultivation regime before AD 1830 may have been identified from the patterns of pollen concentration and preservation in the profiles. © 2008 Elsevier B.V. All rights reserved.

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The spread of nonindigenous species into new habitats is having a drastic effect on natural ecosystems and represents an increasing threat to global biodiversity. In the marine environment, where data on the movement of invasive species is scarce, the spread of alien seaweeds represents a particular problem. We have employed a combination of plastid microsatellite markers and DNA sequence data from three regions of the plastid genome to trace the invasive history of the green alga Codium fragile ssp. tomentosoides. Extremely low levels of genetic variation were detected, with only four haplotypes present in the species’ native range in Japan and only two of these found in introduced populations. These invasive populations displayed a high level of geographical structuring of haplotypes, with one haplotype localized in the Mediterranean and the other found in Northwest Atlantic, northern European and South Pacific populations. Consequently, we postulate that there have been at least two separate introductions of C. fragile ssp. tomentosoides from its native range in the North Pacific.

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This paper presents a new review of our knowledge of the ancient forest beetle fauna from Holocene archaeological and palaeoecological sites in Great Britain and Ireland. It examines the colonisation, dispersal and decline of beetle species, highlighting the scale and nature of human activities in the shaping of the landscape of the British Isles. In particular, the paper discusses effects upon the insect fauna, and examines in detail the fossil record from the Humberhead Levels, eastern England. It discusses the local extirpation of up to 40 species in Britain and 15 species in Ireland. An evaluation of the timing of extirpations is made, suggesting that many species in Britain disappear from the fossil record between c. 3000 cal BC and 1000 cal BC (c. 5000-3000 cal BP), although some taxa may well have survived until considerably later. In Ireland, there are two distinct trends, with a group of species which seem to be absent after c. 2000 cal BC (c. 4000 cal BP) and a further group which survives until at least as late as the medieval period. The final clearance of the Irish landscape over the last few hundred years was so dramatic, however, that some species which are not especially unusual in a British context were decimated. Reasons behind the extirpation of taxa are examined in detail, and include a combination of forest clearance and human activities, isolation of populations, lack of temporal continuity of habitats, edaphic and competition factors affecting distribution of host trees (particularly pine), lack of forest fires and a decline in open forest systems. The role of climate change in extirpations is also evaluated. Consideration is given to the significance of these specialised ancient forest inhabitants in Ireland in the absence of an early Holocene land-bridge which suggests that colonisation was aided by other mechanisms, such as human activities and wood-rafting. Finally, the paper discusses the Continental origins of the British and Irish fauna and its hosts and the role played by European glacial refugia.

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Investigations of geomorphology, geoarchaeology, pollen, palynofacies, and charcoal indicate the comparative scales and significance of palaeoenvironmental changes throughout the Holocene at the junction between the hyper-arid hot Wadi â??Arabah desert and the front of the Mediterranean-belt Mountains of Edom in southern Jordan through a series of climatic changes and episodes of intense mining and smelting of copper ores. Early Holocene alluviation followed the impact of Neolithic grazers but climate drove fluvial geomorphic change in the Late Holocene, with a major arid episode corresponding chronologically with the â??Little Ice Ageâ?? causing widespread alluviation. The harvesting of wood for charcoal may have been sufficiently intense and widespread to affect the capacity of intensively harvested tree species to respond to a period of greater precipitation deduced for the Roman-Byzantine period - a property that affects both taphonomic and biogeographical bases for the interpretation of palynological evidence from arid-lands with substantial industrial histories. Studies of palynofacies have provided a record of human and climatic causes of soil erosion, and the changing intensity of the use of fire over time. The patterns of vegetational, climatic change and geomorphic changes are set out for this area for the last 8000 years.

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A 1.2 m sediment core from Lake Forsyth, Canterbury, New Zealand, records the development of the catchment/lake system over the last 7000 years, and its response to anthropogenic disturbance following European settlement c. 1840 AD. Pollen was used to reconstruct catchment vegetation history, while foraminifera, chironomids, Trichoptera, and the abundance of Pediastrum simplex colonies were used to infer past environmental conditions within the lake. The basal 30 cm of core records the transition of the Lake Forsyth Basin from a tidal embayment to a brackish coastal lake. Timing of closure of the lake mouth could not be accurately determined, but it appears that Lake Forsyth had stabilised as a slightly brackish, oligo mesotrophic shallow lake by about 500 years BP. Major deforestation occurred on Banks Peninsula between 1860 AD and 1890 AD. This deforestation is marked by the rapid decline in the main canopy trees (Prumnopitys taxifolia (matai) and Podocarpus totara/hallii (totara/mountain totara), an increase in charcoal, and the appearance of grasses. At around 1895 AD, pine appears in the record while a willow (Salix spp.) appears somewhat later. Redundancy analysis (RDA) of the pollen and aquatic species data revealed a significant relationship between regional vegetation and the abundance of aquatic taxa, with the percentage if disturbance pollen explaining most (14.8%) of the constrained variation in the aquatic species data. Principle components analysis (PCA) of aquatic species data revealed that the most significant period of rapid biological change in the lakes history corresponded to the main period of human disturbance in the catchment. Deforestation led to increased sediment and nutrient input into the lake which was accompanied by a major reduction in salinity. These changes are inferred from the appearance and proliferation of freshwater algae (Pediastrum simplex), an increase in abundance and diversity of chironomids, and the abundance of cases and remains from the larvae of the caddisfly, Oecetis unicolor. Eutrophication accompanied by increasing salinity of the lake is inferred from a significant peak and then decline of P. simplex, and a reduction in the abundance and diversity of aquatic invertebrates. The artificial opening of the lake to the Pacific Ocean, which began in the late 1800s, is the likely cause of the recent increase in salinity. An increase in salinity may have also encouraged blooms of the halotolerant and hepatotoxic cyanobacteria Nodularia spumigena.

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The recently discovered aging-dependent large accumulation of point mutations in the human fibroblast mtDNA control region raised the question of their occurrence in postmitotic tissues. In the present work, analysis of biopsied or autopsied human skeletal muscle revealed the absence or only minimal presence of those mutations. By contrast, surprisingly, most of 26 individuals 53 to 92 years old, without a known history of neuromuscular disease, exhibited at mtDNA replication control sites in muscle an accumulation of two new point mutations, i.e., A189G and T408A, which were absent or marginally present in 19 individuals younger than 34 years. These two mutations were not found in fibroblasts from 22 subjects 64 to 101 years of age (T408A), or were present only in three subjects in very low amounts (A189G). Furthermore, in several older individuals exhibiting an accumulation in muscle of one or both of these mutations, they were nearly absent in other tissues, whereas the most frequent fibroblast-specific mutation (T414G) was present in skin, but not in muscle. Among eight additional individuals exhibiting partial denervation of their biopsied muscle, four subjects >80 years old had accumulated the two muscle-specific point mutations, which were, conversely, present at only very low levels in four subjects <or =40 years old. The striking tissue specificity of the muscle mtDNA mutations detected here and their mapping at critical sites for mtDNA replication strongly point to the involvement of a specific mutagenic machinery and to the functional relevance of these mutations.

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With the advent of 'ancient DNA' studies on preserved material of extant and extinct species, museums and herbaria now represent an important although still underutilized resource in molecular ecology. The ability to obtain sequence data from archived specimens can reveal the recent history of cryptic species and introductions. We have analysed extant and herbarium samples of the highly invasive green alga Codium fragile, many over 100 years old, to identify cryptic accessions of the invasive strain known as C. fragile ssp. tomentosoides, which can be identified by a unique haplotype. Molecular characterization of specimens previously identified as native in various regions shows that the invasive tomentosoides strain has been colonizing new habitats across the world for longer than records indicate, in some cases nearly 100 years before it was noticed. It can now be found in the ranges of all the other native haplotypes detected, several of which correspond to recognized subspecies. Within regions in the southern hemisphere there was a greater diversity of haplotypes than in the northern hemisphere, probably as a result of dispersal by the Antarctic Circumpolar Current. The findings of this study highlight the importance of herbaria in preserving contemporaneous records of invasions as they occur, especially when invasive taxa are cryptic.