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Bos KI Schuenemann VJ Golding GB Burbano HA Waglechner N Coombes BK McPhee JB DeWitte SN Meyer M Schmedes S Wood J Earn DJ Herring DA Bauer P Poinar HN Krause J 《Nature》2011,478(7370):506-510
Technological advances in DNA recovery and sequencing have drastically expanded the scope of genetic analyses of ancient specimens to the extent that full genomic investigations are now feasible and are quickly becoming standard. This trend has important implications for infectious disease research because genomic data from ancient microbes may help to elucidate mechanisms of pathogen evolution and adaptation for emerging and re-emerging infections. Here we report a reconstructed ancient genome of Yersinia pestis at 30-fold average coverage from Black Death victims securely dated to episodes of pestilence-associated mortality in London, England, 1348-1350. Genetic architecture and phylogenetic analysis indicate that the ancient organism is ancestral to most extant strains and sits very close to the ancestral node of all Y. pestis commonly associated with human infection. Temporal estimates suggest that the Black Death of 1347-1351 was the main historical event responsible for the introduction and widespread dissemination of the ancestor to all currently circulating Y. pestis strains pathogenic to humans, and further indicates that contemporary Y. pestis epidemics have their origins in the medieval era. Comparisons against modern genomes reveal no unique derived positions in the medieval organism, indicating that the perceived increased virulence of the disease during the Black Death may not have been due to bacterial phenotype. These findings support the notion that factors other than microbial genetics, such as environment, vector dynamics and host susceptibility, should be at the forefront of epidemiological discussions regarding emerging Y. pestis infections. 相似文献
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A SUMOylation-defective MITF germline mutation predisposes to melanoma and renal carcinoma 总被引:1,自引:0,他引:1
Bertolotto C Lesueur F Giuliano S Strub T de Lichy M Bille K Dessen P d'Hayer B Mohamdi H Remenieras A Maubec E de la Fouchardière A Molinié V Vabres P Dalle S Poulalhon N Martin-Denavit T Thomas L Andry-Benzaquen P Dupin N Boitier F Rossi A Perrot JL Labeille B Robert C Escudier B Caron O Brugières L Saule S Gardie B Gad S Richard S Couturier J Teh BT Ghiorzo P Pastorino L Puig S Badenas C Olsson H Ingvar C Rouleau E Lidereau R Bahadoran P Vielh P Corda E Blanché H Zelenika D 《Nature》2011,480(7375):94-98
276.
One billion people depend on seafood as their primary source of protein and 25% of the world's total animal protein comes from fisheries. Yet a third of fish stocks worldwide are overexploited or depleted. Using individual case studies, many have argued that community-based co-management should prevent the tragedy of the commons because cooperative management by fishers, managers and scientists often results in sustainable fisheries. However, general and multidisciplinary evaluations of co-management regimes and the conditions for social, economic and ecological success within such regimes are lacking. Here we examine 130 co-managed fisheries in a wide range of countries with different degrees of development, ecosystems, fishing sectors and type of resources. We identified strong leadership as the most important attribute contributing to success, followed by individual or community quotas, social cohesion and protected areas. Less important conditions included enforcement mechanisms, long-term management policies and life history of the resources. Fisheries were most successful when at least eight co-management attributes were present, showing a strong positive relationship between the number of these attributes and success, owing to redundancy in management regulations. Our results demonstrate the critical importance of prominent community leaders and robust social capital, combined with clear incentives through catch shares and conservation benefits derived from protected areas, for successfully managing aquatic resources and securing the livelihoods of communities depending on them. Our study offers hope that co-management, the only realistic solution for the majority of the world's fisheries, can solve many of the problems facing global fisheries. 相似文献
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Prud'homme B Minervino C Hocine M Cande JD Aouane A Dufour HD Kassner VA Gompel N 《Nature》2011,473(7345):83-86
Body plans, which characterize the anatomical organization of animal groups of high taxonomic rank, often evolve by the reduction or loss of appendages (limbs in vertebrates and legs and wings in insects, for example). In contrast, the addition of new features is extremely rare and is thought to be heavily constrained, although the nature of the constraints remains elusive. Here we show that the treehopper (Membracidae) 'helmet' is actually an appendage, a wing serial homologue on the first thoracic segment. This innovation in the insect body plan is an unprecedented situation in 250 Myr of insect evolution. We provide evidence suggesting that the helmet arose by escaping the ancestral repression of wing formation imparted by a member of the Hox gene family, which sculpts the number and pattern of appendages along the body axis. Moreover, we propose that the exceptional morphological diversification of the helmet was possible because, in contrast to the wings, it escaped the stringent functional requirements imposed by flight. This example illustrates how complex morphological structures can arise by the expression of ancestral developmental potentials and fuel the morphological diversification of an evolutionary lineage. 相似文献
279.
Cerling TE Wynn JG Andanje SA Bird MI Korir DK Levin NE Mace W Macharia AN Quade J Remien CH 《Nature》2011,476(7358):51-56
The role of African savannahs in the evolution of early hominins has been debated for nearly a century. Resolution of this issue has been hindered by difficulty in quantifying the fraction of woody cover in the fossil record. Here we show that the fraction of woody cover in tropical ecosystems can be quantified using stable carbon isotopes in soils. Furthermore, we use fossil soils from hominin sites in the Awash and Omo-Turkana basins in eastern Africa to reconstruct the fraction of woody cover since the Late Miocene epoch (about 7 million years ago). (13)C/(12)C ratio data from 1,300 palaeosols at or adjacent to hominin sites dating to at least 6 million years ago show that woody cover was predominantly less than ~40% at most sites. These data point to the prevalence of open environments at the majority of hominin fossil sites in eastern Africa over the past 6 million years. 相似文献
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