The conservation status of 845 zooxanthellate reefbuilding coral species have been assessed using IUCN Red List Criteria. Of the 704 species that could be assigned conservation status, 32.8% are in categories with elevated risk of extinction. Declines in abundance are associated with bleaching and diseases driven by elevated sea surface temperatures, with extinction risk further exacerbated by local-scale anthropogenic disturbances. The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds most terrestrial groups. The Caribbean has the largest proportion of corals in high extinction risk categories while the Coral Triangle (western Pacific) has the highest proportion of species in all categories of elevated extinction risk. Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures.Coral reefs harbor the highest concentration of marine biodiversity. They have high esthetic, recreational and resource values that have prompted close scientific scrutiny, including long-term monitoring (1, 2) and face increasing threats at local and global scales. Globally, rapid build-up of carbon dioxide (and other greenhouse gases) in the atmosphere is leading to both rising sea surface temperatures (with an increased likelihood of mass coral bleaching and mortality) and acidification (8). Ocean acidification is reducing ocean carbonate ion concentrations and the ability of corals to build skeletons (9). Local threats include human disturbances such as increased coastal development, sedimentation resulting poor land-use and watershed management, sewage discharges, nutrient loading and eutrophication from agrochemicals, coral mining, and over fishing (1-7). Local anthropogenic impacts reduce the resilience of corals to withstand global threats, resulting in a

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SUMMARYAnts are central place foragers and use multiple information sources to navigate between the nest and feeding sites. Individual ants rapidly learn a route, and often prioritize memory over pheromone trails when tested on a simple trail with a single bifurcation. However, in nature, ants often forage at locations that are reached via more complex routes with multiple trail bifurcations. Such routes may be more difficult to learn, and thus ants would benefit from additional information. We hypothesized that trail pheromones play a more significant role in ant foraging on complex routes, either by assisting in navigation or route learning or both. We studied Lasius niger workers foraging on a doubly bifurcating trail with four end points. Route learning was slower and errors greater on alternating (e.g. left-right) versus repeating routes (e.g. left-left), with error rates of 32 and 3%, respectively. However, errors on alternating routes decreased by 30% when trail pheromone was present. Trail pheromones also aid route learning, leading to reduced errors in subsequent journeys without pheromone. If an experienced forager makes an error when returning to a food source, it reacts by increasing pheromone deposition on the return journey. In addition, high levels of trail pheromone suppress further pheromone deposition. This negative feedback mechanism may act to conserve pheromone or to regulate recruitment. Taken together, these results demonstrate further complexity and sophistication in the foraging system of ant colonies, especially in the role of trail pheromones and their relationship with learning and the use of private information (memory) in a complex environment.

A consistent clinical feature of amyotrophic lateral sclerosis (ALS) is the sparing of eye movements and the function of external sphincters, with corresponding preservation of motor neurons in the brainstem oculomotor nuclei, and of Onuf’s nucleus in the sacral spinal cord. Studying the differences in properties of neurons that are vulnerable and resistant to the disease process in ALS may provide insights into the mechanisms of neuronal degeneration, and identify targets for therapeutic manipulation. We used microarray analysis to determine the differences in gene expression between oculomotor and spinal motor neurons, isolated by laser capture microdissection from the midbrain and spinal cord of neurologically normal human controls. We compared these to transcriptional profiles of oculomotor nuclei and spinal cord from rat and mouse, obtained from the GEO omnibus database. We show that oculomotor neurons have a distinct transcriptional profile, with significant differential expression of 1,757 named genes (q < 0.001). Differentially expressed genes are enriched for the functional categories of synaptic transmission, ubiquitin-dependent proteolysis, mitochondrial function, transcriptional regulation, immune system functions, and the extracellular matrix. Marked differences are seen, across the three species, in genes with a function in synaptic transmission, including several glutamate and GABA receptor subunits. Using patch clamp recording in acute spinal and brainstem slices, we show that resistant oculomotor neurons show a reduced AMPA-mediated inward calcium current, and a higher GABA-mediated chloride current, than vulnerable spinal motor neurons. The findings suggest that reduced susceptibility to excitotoxicity, mediated in part through enhanced GABAergic transmission, is an important determinant of the relative resistance of oculomotor neurons to degeneration in ALS.Electronic supplementary materialThe online version of this article (doi:10.1007/s00401-012-1058-5) contains supplementary material, which is available to authorized users.

This article troubles the established discourse of free choice and free play in early childhood education, and develops post-structural approaches to theorising children's agency in the context of institutional and relational power structures. It is widely accepted that planning a curriculum based on children's needs, interests and patterns of learning promotes agency, self-regulation and control. However, contemporary research extends this discourse through critical examination of child-centred and developmental perspectives, and by theorising children's agency as a means of enacting power relationships in play. Using naturalistic, interpretive methods for documenting children's choices of play activities, this small-scale study focuses on 10 children in an Early Years Foundation Stage setting in England. Combining contemporary sociocultural and post-structural theories, the findings indicate that children's choices are situated within shifting power structures and relationships, involving conflict, negotiation, resistance and subversion. These activities create opportunities for exercising and affirming group and individual agency. The study raises critical questions about how children make and manage their choices, and examines the implications for policy and practice in light of restrictive curriculum frameworks.

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A continuing struggle over curriculum in early childhood education is evident in contemporary research and debate at national and international levels. This reflects the dominant influence of developmental psychology in international discourses, and in policy frameworks that determine approaches to curriculum, pedagogy and assessment. Focusing on early childhood education, we argue that this struggle generates critical questions about three significant themes within curriculum theory: content, coherence and control. We outline two positions from which these themes can be understood: Developmental and Educational Psychology and contemporary policy frameworks. We argue that within and between these positions curriculum content, coherence, and control are viewed in different and sometimes oppositional ways. Following this analysis, we propose that a focus on 'working theories' as a third position offers possibilities for addressing some of these continuing struggles, by exploring different implications for how content, coherence, and control might be understood. We conclude that asking critical questions of curriculum in early childhood education is a necessary endeavor to develop alternative theoretical frameworks for understanding the ways in which curriculum can be considered alongside pedagogy, assessment, play and learning.

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