Multiple drivers of decline in the global status of freshwater crayfish (Decapoda: Astacidea)

International audienceRates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world's 590 freshwater crayfish species using the IUCN Categories and Criteria and found 32% of all species are threatened with extinction. The level of extinction risk differed between families, with proportionally more threatened species in the Parastacidae and Astacidae than in the Cambaridae. Four described species were Extinct and 21% were assessed as Data Deficient. There was geographical variation in the dominant threats affecting the main centres of crayfish diversity. The majority of threatened US and Mexican species face threats associated with urban development, pollution, damming and water management. Conversely, the majority of Australian threatened species are affected by climate change, harvesting, agriculture and invasive species. Only a small proportion of crayfish are found within the boundaries of protected areas, suggesting that alternative means of long-term protection will be required. Our study highlights many of the significant challenges yet to come for freshwater biodiversity unless conservation planning shifts from a reactive to proactive approach

Strategic canonisation : sanctity, popular culture and the Catholic Church

In his twenty-seven year reign (1978-2005), Pope John Paul II created not only more saints than any other pope in history, but also more saints than all the other popes put together since Pope Urban VIII centralised control of saint-making in 1634. This article argues that the elevation of ‘celebrity saints’, such as Padre Pio and Mother Theresa, can be seen as an attempt on the part of the Catholic Church to strengthen its presence within the arena of popular culture. Through a sustained programme of ‘strategic canonization’, John Paul II promoted models of sanctity that conveyed very clear social and political messages. Such messages were amplified through extensive Catholic media and, where ‘celebrity saints’ were involved, through the secular media too. These processes are analysed first, in relation to the general area of sexual politics; and secondly, to the Church’s historic relationship with Nazism. Whilst John Paul’s programme may not have achieved all that it intended, it clearly demonstrated the Catholic Church’s unique capacity to reinvent very old forms of cultural policy for changing times

MAS as complex systems: A view on the role of declarative approaches

The ever growing complexity of software systems calls for new forms of understanding and conceptual tools. It has been argued that some "Laws of Complexity" exist, which govern the behaviour of complex systems of any sort, from natural to artificial ones. Along this line, in this paper we draw from the most recent findings of evolutionary biology to develop an original view over Multiagent Systems (MAS). A schema for a "layered", hierarchical view of MAS is introduced, aimed at providing computer scientists and engineers with a powerful conceptual framework for MAS observation/modelling/construction. We first introduce the three levels of the hierarchy in general, and then show how they impact on current proposals for methodologies of agentoriented analysis and design. Finally, we exploit the hierarchy to provide an overall organised view over declarative approaches to MAS, by using as a reference those presented in the other contributions in this book. On the one hand, a hierarchical view allows the many different approaches to be distinguished, classified and possibly compared. On the other hand, it makes it possible to reveal the richness and diversity of declarative models and technologies for MAS, as well as to show the multiplicity of ways in which they impact on MAS modelling and engineering