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Metacommunity theory and its constituent theory of island biogeography (TIB) have the potential to unify ecology across different scales. The TIB has been successful in predicting alpha diversity patterns, such as species-area relationships and species-abundance distributions, but lags behind in predicting spatial beta diversity patterns. In this study we use island biogeography theory as the starting point to integrate spatial beta diversity patterns into metacommunity theory. We first derive theoretical predictions for the expected beta diversity patterns under the classic MacArthur and Wilson framework, where all species have equal colonization and extinction rates. We then test these predictions for the avian community composition of 42 islands (and 93 species) in Thousand Island Lake, China. Our theoretical results corroborate that longer distance and smaller area lead to higher beta diversity and further reveal that pairwise beta diversity is independent of the size of the mainland species pool. We also find that for the partitioned pairwise beta diversity components, the turnover component increases with the ratio of extinction rates and colonization rates, while the nestedness component is a unimodal function of the ratio of extinction rates and colonization rates. For the empirical island system, we find that beta diversity patterns better distinguish a species-equivalent model from a species-nonequivalent model than alpha diversity patterns. Our findings suggest that beta diversity patterns provide a powerful tool in detecting nonneutral processes, and our model has the potential to incorporate more biological realism in future analyses. [ABSTRACT FROM AUTHOR]

Barro Colorado Island (BCI), Panama, may be the most studied tropical forest in the world. A 1,560-hectare island created by the flooding of the Panama Canal, BCI became a nature reserve and biological research station in 1923. Contemporaries saw the island as an "ark" preserving a sample of primeval tropical nature for scientific study. BCI was not simply "set aside," however. The project of making it a place for science significantly reshaped the island through the twentieth century. This essay demonstrates that BCI was constructed specifically to allow long-term observation of tropical organisms-their complex behaviors, life histories, population dynamics, and changing species composition. An evolving system of monitoring and information technology transformed the island into a living scientific "archive," in which the landscape became both an object and a repository of scientific knowledge. As a research site, BCI enabled a long-term, place-based form of collective empiricism, focused on the study of the ecology of a single tropical island. This essay articulates tropical ecology as a "science of the archive" in order to examine the origins of practices of environmental surveillance that have become central to debates about global change and conservation. [ABSTRACT FROM AUTHOR]

The defensive compounds produced by pygidial glands of adult tiger beetles were analyzed for 83 species from North America, India, and Peru. Benzal-dehyde, the most common defensive compound detected, was found in 39 species. The presence of this compound, which has evolved independently in only a few other arthropod groups, indicates a cyanogenic precursor. Each of these 83 tiger beetle species occurred primarily in one of seven distinct habitats, such as forest floor, sand dune, water edge, and saline flat. All 83 species were also grouped according to genitalic similarities into distinct systematic taxa that represent closely related species. We predicted two alternative patterns of benzaldehyde presence among these tiger beetle species. (1) Through historical influences of systematic relatedness, benzaldehyde should be either present or absent nonrandomly among closely related species regardless of habitat and associated ecological similarities and differences. (2) Through convergence of defense against similar predators within each habitat type, benzaldehyde should be present nonrandomly among species in some habitats and absent nonrandomly in others, regardless of geographical location and systematic relationship. Our results show that in systematic groups with four or more species analyzed, 34 of 39 pooled species were consistent within a group for the presence or absence of benzaldehyde, regardless of habitat type (P < 0.001). However, for only one of the seven habitats (sandy water edge) was benzaldehyde present nonrandomly regardless of geographical location and systematic relationship. We conclude that historical (phylogenetic) factors are likely to be generally important in interpreting ecological data, as either alternative or interactive processes. [ABSTRACT FROM AUTHOR]

The author discusses a study by Ben Orlove and colleagues regarding climate change. Topics include the undivided shape of climate change across ice, island, and desert, the impact of geographies' hierarchical orderings on birth or residence, and concerns regarding the possible disappearance of islands and the condition of Islophilia.

The author discusses an article regarding the identification of global geographic attention to risk and social vulnerability of climate. Topics include the impact of Arctic and island climate change on polar bears and islands, the vulnerability of poor drylands amidst ordinary climate change and variability, and adaptation fund set up by the United Nations (UN) Framework Convention on Climate Change.