J S Clark

..With this potential come new challenges, including some that are specific and technical and others that are general and will involve reexamination of the role of inference and prediction...

..This mechanism can explain coexistence of species that would not occur with simple, low-dimensional tradeoff scenarios...

..Models lacking explicit species can make useful predictions, but this does not support neutral theory. I provide s suggestions that could help reduce confusion generated by the debate...

..To understand how this pattern of variation is related to niche variables, we analyzed responses to canopy gaps, long viewed as a key variable responsible for species coexistence...

..We show how to identify when aggregation is the problem, where it has caused controversy, and propose three ways to address it...

..Our examples involve soil moisture and sap flux, but we discuss broader application of the approach, including its implications for network design...

..Results are consistent with theory predicting that coexistence depends on competition being stronger within than between species, shown here by analysis of individual-level responses to environmental fluctuation...

..Finally, I suggest that the dramatic shift in ecological research to focus on neutrality could have a cost in terms of scientific understanding and relevance to real biodiversity threats...

..An example involving multiple species and multiple stands with tree-ring data and up to 14 years of tree census data illustrates how different levels of information at the tree and stand level contribute to inference and prediction...

..Interdisciplinary linkages are necessary because of the climate and societal controls on ecosystems, the feedbacks involving social change, and the decision-making relevance of forecasts...

..By contrast with the neutral prediction of increasing variance among sites over time, we show that variances in post-Glacial tree abundances among sites stabilize rapidly, and abundances remain coherent over broad geographical scales...

..However, by aggregating in specific ways (over individuals, years, and other input variables), we provide ways to summarize and rank species in terms of their risks from climate change...

..9.3 m), suggesting that, under some circumstances, oaks may be less dispersal-limited than is commonly thought, with a greater potential for range shifts in response to climate change...

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..This model moves away from traditional random walks, and instead focuses inference on how moving animals with complex behavior interact with their landscape and make choices about its suitability...

..This reproductive response to future increases in atmospheric CO2 concentration is expected to change loblolly dispersal and recruitment patterns...

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..Accordingly, the effects of global warming from increasing greenhouse gases will be superimposed on this natural variability of drought...

..Thus, unless the strength of density-dependent mortality varies with latitude, this mechanism is not likely to explain the high diversity of tropical forests...

..Current climate change scenarios and their underlying uncertainty make studies such as this one crucial for understanding the dynamics of ungulate populations and their conservation...

..Our results indicate that Toxicodendron taxa will become more abundant and more "toxic" in the future, potentially affecting global forest dynamics and human health...

..Our data suggest a small CO2 fertilization effect on tree productivity, and the possibility of reduced carbon accumulation rates relative to today's forests due to changes in species composition...

..rubra (17% of sites). Tradeoffs between seedling performance and fecundity may promote the diversity of seedling regeneration by increasing the probability of inferior competitors capturing regeneration sites...