Genetic structure at range edge: Low diversity and high inbreeding in Southeast Asian mangrove (Avicennia marina) populations

Understanding the genetic composition and mating systems of edge populations provides important insights into the environmental and demographic factors shaping species’ distribution ranges. We analysed samples of the mangrove Avicennia marina from Vietnam, northern Philippines and Australia, with microsatellite markers. We compared genetic diversity and structure in edge (Southeast Asia, and Southern Australia) and core (North and Eastern Australia) populations, and also compared our results with previously published data from core and southern edge populations. Comparisons highlighted significantly reduced gene diversity and higher genetic structure in both margins compared to core populations, which can be attributed to very low effective population size, pollinator scarcity and high environmental pressure at distribution margins. The estimated level of inbreeding was significantly higher in northeastern populations compared to core and southern populations. This suggests that despite the high genetic load usually associated with inbreeding, inbreeding or even selfing may be advantageous in margin habitats due to the possible advantages of reproductive assurance, or local adaptation. The very high level of genetic structure and inbreeding show that populations of A. marina are functioning as independent evolutionary units more than as components of a metapopulation system connected by gene flow. The combinations of those characteristics make these peripheral populations likely to develop local adaptations and therefore to be of particular interest for conservation strategies as well as for adaptation to possible future environmental changes.

Environmental ethics: philosophy, ecology and other species

Pressure on the environment has increased in step with economic growth and the mass consumption that fueled rising gross domestic product throughout the twentieth century. Both growth and ecological crises have attained a global reach, challenging our established notions of cause and effect, and our framing of problems and solutions. Accordingly, global environmental politics has witnessed major changes and significant "rescaling" in its "locus, agency and scope" (Andonova and Mitchell2010: 257). Both dimensions of global environmental politics - politics and governance, and the ecological problems that are the subject matter of global environmental politics - are being reinterpreted due to increasing complexity, interconnectedness and interdependence. Accordingly, the range of actors and disciplines that infom1 global environmental politics and contribute to framing global environmental problems is widening, in an acknowledgment of inescapable pluralism.

Book review: Philosophy and the city: classic to contemporary writings

Book Review: Philosophy and the City: Classic to Contemporary Writings Sharon M. Meagher (Ed.), 2007 Albany, NY: State University of New York Press 309 pp. US$75.50 hardback; US$24.95 paperback ISBN 978 0 7914 7308 5 paperback; 978 0 7914 7307 8 hardback

Colour Sensation and Empathy: Arthur Schopenhauer's Negative Philosophy and Colour Theory as the Basis of an Elemental Colour Architecture

Arthur Schopenhauer proposed a theory of colour as a consequence of his first hand knowledge of J.W. Goethe’s experiments with color phenomena. This colour theory can be used to explore an interesting proposition Schopenhauer made about architecture. For Schopenhauer, architecture is about feelings, not about functions or forms, its purpose as an art is to reveal the principles of primitive forces, specifically gravity and rigidity. For Schopenhauer, architecture expresses these forces in the poised equilibrium of massive structures built out of stone. Schopenhauer was inclined to believed that architecture had already achieved its most perfect expression in Greek temple architecture. However; he did offer one possibility for architectural research: this was the suggestion that architecture was also concerned with the expression of light. It seems never to have occurred to Schopenhauer to use his colour theory to speculate about light in architecture. This paper explores some of the implications of Schopenhauer’s theory of colour for his aesthetics of architecture?

Modernism and Magic: Experiments with Spiritualism, Philosophy and the Occult, paperback

The book explores the aesthetic and political implications of the relationship between magic and mimesis in the work of those early twentieth-century writers, artists and filmmakers who were most self-consciously experimental, including James Joyce, Ezra Pound, Dziga Vertov and Sergei Eisenstein.