2 resultados para Amplificação de gens

em CentAUR: Central Archive University of Reading - UK


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There are over 700 species of fig trees in the tropics and several thousand species of fig wasps are associated with their syconia (inflorescences). These wasps comprise a monophyletic family of fig pollinators and several diverse lineages of non-pollinating wasps. The pollinator larvae gall fig flowers, while larvae of non-pollinating species either initiate their own galls or parasitise the galls of other wasps. A single fig species has 1-4 pollinator species and also hosts up to 30 non-pollinating wasp species. Most wasps show a high degree of host plant specificity and are known from only a single fig species. However, in some cases wasps may be shared across closely related fig species. There is impressive morphological coevolution between figs and fig wasps and this, combined with a high degree of partner specificity, led to the expectation that figs and pollinators have cospeciated extensively. Comparison of deep phylogenies supports long-term codivergence of figs and pollinators, but also suggests that some host shifts have occurred. Phylogenies of more closely related species do not match perfectly and may even be incongruent, suggesting significant roles for processes other than strict cospeciation. Combined with recent evidence on host specificity patterns, this suggests that pollinator wasps may often speciate by host shifts between closely related figs, or by duplication (the wasp speciates but the fig doesn't). The frequencies and biological details of these different modes of speciation invite further study. Far less is known about speciation in non-pollinating fig wasps. Some lineages have probably coevolved with figs and pollinators for most of the evolutionary history of the symbiosis, while others appear to be more recent colonisers. Many species appear to be highly host plant specific, but those that lay eggs through the fig wall without entering the syconium (the majority of species) may be subject to fewer constraints on host-shifting than pollinators. There is evidence for substantial host shifting in at least one gens, but also evidence for ecological speciation on the same host plant by niche shifts in other cases. Finally, recent work has begun to address the issue of “community phylogeny” and provided evidence for long-term co-divergence of multiple pollinating and non-pollinating wasp lineages with their host figs.

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Profit, embezzlement, restitution. The role of the traitants in the Nine Years War and Chamillart’s tax on financial benefits The aim of this article is to revisit the question of the financiers in Old Regime France. It starts with an analysis of the discourses about the financiers under the Absolute monarchy that underlines the complexity of their relationship with the government and the public. It then reviews the secondary literature and highlights the existence of competing historical interpretations (functional, political, utilitarian), which raise the question of their overall capacity to account for the role and impact of the financiers at different times. On this ground, the article focuses on a specific group of financiers, the so-called traitants d’affaires extraordinaires, during the Nine Years War. Further to a description of the specific role and scope of the activities of the various financiers responsible for helping the monarchy to raise the funds it needed to pay for its peace and wartime expenditure, the article examines the conditions and profits granted by the king in his contracts with the traitants whose services were hired for the purpose of selling royal offices in the public and advancing the revenue to the Treasury. It also explores the contractual arrangements of the companies established by the financiers to manage their operations as well as the rights and the responsibilities of their various stakeholders. These bases being laid, the article relies on the administrative correspondence relating to the traités during the Nine Years War to address a range of issues, in particular the extent to which these contracts, and other control procedures, were robust enough to deter fraud. The accounts of two traitants’ companies offer an opportunity to analyse and compare the structure of their income and expenditure (including the volume and cost of the promissory notes sold in the public to finance their payments to the Treasury), to explore the strategies of the contractors, to calculate their net profits and further discuss the problem of embezzlement. The article ends with the study of the context and debates which led to the introduction by finance minister Michel Chamillart, in 1700, of a shortfall tax on the financial profits of the gens d’affaires or traitants, the method used to determine its rate (50 % of the net benefits), its distribution among the various stakeholders (including the bailleurs de fonds or backers), and the related procedures. In total, the article argues that the relationship between the monarchy, society and the financiers under the Ancien Regime was not static and, therefore, suggests that the broad question of control and fraud must be examined against changing circumstances. With regard specifically to the Nine Years War, the article concludes that within the constraints of the Absolute monarchy, contractors offered valuable services by raising capital for the benefit of a king who ruled over a country which, at the time, was by far the wealthiest in Europe, and where ministers failed to foresee long wars of attrition and whose financial strategy was limited by the very existence of privilege. Overall, the traités were too costly to be a viable system of war financing. In these conditions, the substantial fortunes made by a handful of very successful traitants suffice to explain that the government easily gave in to public criticism against the wealth of the financiers and felt compelled, when peace resumed, to cancel the advantageous conditions offered in the treaties by taxing financial profits.