Climatic niche evolution in new world monkeys (Platyrrhini)

Despite considerable interest in recent years on species distribution modeling and phylogenetic niche conservatism, little is known about the way in which climatic niches change over evolutionary time. This knowledge is of major importance to understand the mechanisms underlying limits of species distributions, as well as to infer how different lineages might be affected by anthropogenic climate change. In this study we investigate the tempo and mode climatic niche evolution in New World monkeys (Platyrrhini). Climatic conditions found throughout the distribution of 140 primate species were investigated using a principal component analysis, which indicated that mean temperature (particularly during the winter) is the most important climatic correlate of platyrrhine geographical distributions, accounting for nearly half of the interspecific variation in climatic niches. The effects of precipitation were associated with the second principal component, particularly with respect to the dry season. When models of trait evolution were fit to scores on each of the principal component axes, significant phylogenetic signal was detected for PC1 scores, but not for PC2 scores. Interestingly, although all platyrrhine families occupied comparable regions of climatic space, some aotid species such as Aotus lemurinus, A. jorgehernandezi, and A. miconax show highly distinctive climatic niches associated with drier conditions (high PC2 scores). This shift might have been made possible by their nocturnal habits, which could serve as an exaptation that allow them to be less constrained by humidity during the night. These results underscore the usefulness of investigating explicitly the tempo and mode o

Preventing the introduction of meticillin-resistant Staphylococcus aureus into hospitals

The objective of this review was to provide an up-to-date account of the interventions used to prevent the introduction of meticillin-resistant Staphylococcus aureus (MRSA) from the expanding community and livestock reservoirs into hospitals in the USA, Denmark, The Netherlands and Western Australia. A review of existing literature and local guidelines for the management of MRSA in hospitals was performed. In Denmark, The Netherlands and Western Australia, where the prevalence of MRSA is relatively low, targeted admission screening and isolation of predefined high-risk populations have been used for several decades to successfully control MRSA in the hospital. Furthermore, in Denmark and The Netherlands, all identified MRSA carriers undergo routine decolonisation, whereas only carriers of particularly transmissible or virulent MRSA clones are subjected to decolonisation in Western Australia. In the USA, which continues to be a high-prevalence MRSA country, policies vary by state and even by hospital, and whilst guidelines from professional organisations provide a framework for infection control practices, these guidelines lack the authority of a legislative mandate. In conclusion, the changing epidemiology of MRSA, exemplified by the recent emergence of MRSA in the community and in food animals, makes it increasingly difficult to accurately identify specific high-risk groups to screen for MRSA carriage. Understanding the changing epidemiology of MRSA in a local as well as global context is fundamental to prevent the introduction of MRSA into hospitals