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Ecological globalisation, serial depletion and the medieval trade of walrus rostra
The impacts of early ecological globalisation may have had profound economic and environmental consequences for human settlements and animal populations. Here, we review the extent of such historical impacts by investigating the medieval trade of walrus (Odobenus rosmarus rosmarus) ivory. We use an interdisciplinary approach including chaĂźne opĂ©ratoire, ancient DNA (aDNA), stable isotope and zooarchaeological analysis of walrus rostra (skull sections) to identify their biological source and subsequent trade through Indigenous and urban networks. This approach complements and improves the spatial resolution of earlier aDNA observations, and we conclude that almost all medieval European finds of walrus rostra likely derived from Greenland. We further find that shifting urban nodes redistributed the traded ivory and that the latest medieval rostra finds were from smaller, often female, walruses of a distinctive DNA clade, which is especially prevalent in northern Greenland. Our results suggest that more and smaller animals were targeted at increasingly untenable distances, which reflects a classic pattern of resource depletion. We consider how the trade of walrus and elephant ivory intersected, and evaluate the extent to which emergent globalisation and the âresource curseâ contributed to the abandonment of Norse Greenland
The trans-Eurasian crop exchange in prehistory: Discerning pathways from barley phylogeography
A number of crops that are of global importance today, including wheat (Triticum spp) and barley (Hordeum vulgare), were domesticated in Southwest Asia between 10,000 and 11,000 years ago and subsequently spread through the Old World, into Europe, North Africa and eastwards across Eurasia. Their routes of expansion have been a focus of debate and are increasingly being revealed by widespread dating of archaeobotanical remains from across Eurasia. Of particular interest is work by Zhao (2009) who proposed three routes for the spread of wheat into China: firstly, across the Eurasian Steppe, second by sea from India to the east coast of Eurasia and third, along the Hexi Corridor, which forms part of the Silk Road in western China. Molecular genetic analysis of cereal landraces have also elucidated routes of expansion of cereal cultivation and, in addition, have revealed how crops adapted to changing environments as they moved away from their centres of domestication. Genes involved in flowering time genes have been a particular focus of these studies, including the photoperiod response gene Ppd-H1 in barley, which controls flowering in response to increasing day-lengths in the spring. In this paper we present a phylogeographic analysis of Old World landrace and wild barley, through the analysis of a portion of the Ppd-H1 DNA sequence. We discuss the geographic distribution of different haplotypes of this gene across Eurasia in the light of Zhao (2009)'s three routes and what it potentially reveals about trans-Eurasian pathways of contact between early farming communities.This research was conducted under the auspices of the âFood Globalization in Prehistoryâ (FOGLIP, ERC grant number 249642) and âOrigins and Spread of Agriculture in the South West Mediterranean Regionâ (AgriWestMed, ERC Grant Number 230561) research projects, both funded by the European Research Council
From ecological opportunism to multi-cropping: Mapping food globalisation in prehistory
Many of today's major food crops are distributed worldwide. While much of this âfood globalisationâ has resulted from modern trade networks, it has its roots in prehistory. In this paper, we examine cereal crops that moved long distances across the Old World between 5000 and 1500 BC. Drawing together recent archaeological evidence, we are now able to construct a new chronology and biogeography of prehistoric food globalisation. Here we rationalize the evidence for this process within three successive episodes: pre-5000 BC, between 5000 and 2500 BC, and between 2500 and 1500 BC. Each episode can be characterized by distinct biogeographical patterns, social drivers of the crop movements, and ecological constraints upon the crop plants. By 1500 BC, this process of food globalisation had brought together previously isolated agricultural systems, to constitute a new kind of agriculture in which the bringing together of local and exotic crops enables a new form of intensification.The authors are grateful to the European Research Council, under grant 249642, âFood Globalisation in Prehistoryâ (FOGLIP, PI: M. K. Jones); the Leverhulme Trust, under grant f/09717/C, âPioneers of Pan-Asian Contactâ(PPAC, PI: M. K. Jones); the National Science Foundation, under grant 1826727, âThe origins and spread of millet cultivationâ (PI: X. Liu); the Rae and Edith Bennett Travelling Scholarship (P. J. Jones); the International Center for Energy, Environment and Sustainability (InCEES, PI: X. Liu), Washington University in St Louis; and the European Social Fund, under grant 09.3.3-LMT-K-712 âImprovement of researchers' qualification by implementing world-class R&D projectsâ (PI: G. Motuzaite Matuzeviciute) and Darwin College, Cambridge for financial support
Ecology and Transmission of Buruli Ulcer Disease: A Systematic Review
Buruli ulcer is a neglected emerging disease that has recently been reported in some countries as the second most frequent mycobacterial disease in humans after tuberculosis. Cases have been reported from at least 32 countries in Africa (mainly west), Australia, Southeast Asia, China, Central and South America, and the Western Pacific. Large lesions often result in scarring, contractual deformities, amputations, and disabilities, and in Africa, most cases of the disease occur in children between the ages of 4â15 years. This environmental mycobacterium, Mycobacterium ulcerans, is found in communities associated with rivers, swamps, wetlands, and human-linked changes in the aquatic environment, particularly those created as a result of environmental disturbance such as deforestation, dam construction, and agriculture. Buruli ulcer disease is often referred to as the âmysterious diseaseâ because the mode of transmission remains unclear, although several hypotheses have been proposed. The above review reveals that various routes of transmission may occur, varying amongst epidemiological setting and geographic region, and that there may be some role for living agents as reservoirs and as vectors of M. ulcerans, in particular aquatic insects, adult mosquitoes or other biting arthropods. We discuss traditional and non-traditional methods for indicting the roles of living agents as biologically significant reservoirs and/or vectors of pathogens, and suggest an intellectual framework for establishing criteria for transmission. The application of these criteria to the transmission of M. ulcerans presents a significant challenge
ExercĂcio fĂsico, receptores β-adrenĂ©rgicos e resposta vascular Physical exercise, β-adrenergic receptors, and vascular response
O exercĂcio aerĂłbio promove efeitos benĂ©ficos na prevenção e tratamento de doenças como hipertensĂŁo arterial, aterosclerose, insuficiĂȘncia venosa e doença arterial perifĂ©rica. Os receptores β-adrenĂ©rgicos estĂŁo presentes em vĂĄrias cĂ©lulas. No sistema cardiovascular, promovem inotropismo e cronotropismo positivo cardĂaco e relaxamento vascular. Embora os efeitos do exercĂcio tenham sido investigados em receptores cardĂacos, estudos focados nos vasos sĂŁo escassos e controversos. Esta revisĂŁo abordarĂĄ os efeitos do exercĂcio fĂsico sobre os receptores β-adrenĂ©rgicos vasculares em modelos animais e humanos e os mecanismos celulares envolvidos na resposta relaxante. Em geral, os estudos mostram resultantes conflitantes, onde observam diminuição, aumento ou nenhum efeito do exercĂcio fĂsico sobre a resposta relaxante. Assim, os efeitos do exercĂcio na sensibilidade β-adrenĂ©rgica vascular merecem maior atenção, e os resultados mostram que a ĂĄrea de fisiopatologia vascular Ă© um campo aberto para a descoberta de novos compostos e avanços na prĂĄtica clĂnica.<br>Aerobic exercise promotes beneficial effects on the prevention and treatment of diseases such as arterial hypertension, atherosclerosis, venous insufficiency, and peripheral arterial disease. β-adrenergic receptors are present in a variety of cells. In the cardiovascular system, β-adrenergic receptors promote positive inotropic and chronotropic response and vasorelaxation. Although the effect of exercise training has been largely studied in the cardiac tissue, studies focused on the vascular tissue are rare and controversial. This review examines the data from studies using animal and human models to determine the effect of physical exercise on the relaxing response mediated by β-adrenergic receptors as well as the cellular mechanisms involved in this response. Studies have shown reduction, increase, or no effect of physical exercise on the relaxing response mediated by β-adrenergic receptors. Thus, the effects of exercise on the vascular β-adrenergic sensitivity should be more deeply investigated. Furthermore, the physiopathology of the vascular system is an open field for the discovery of new compounds and advances in the clinical practice