Andrew P Hendry

..We solicit your involvement in developing innovative ways of using evolutionary biology to better comprehend and stem the loss of biodiversity...

..Human activities may negatively impact diversification in 'young' adaptive radiations, perhaps by altering adaptive landscapes...

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..Research on sticklebacks has thus revealed complex and shifting interactions between selection, adaptation, mutation and geography during the course of speciation...

..In short, humans are an important agent driving phenotypic change in contemporary populations. Although these changes sometimes have a genetic basis, our analyses suggest a particularly important contribution from phenotypic plasticity...

..The best evidence for IBT and ABT currently comes from salmonid fishes and flowering plants, but we expect that future work will show these processes are more widespread...

..Spatial and temporal variation in G. fortis bimodality suggests a dynamic tug of war among factors such as selection and assortative mating, which may alternatively promote or constrain divergence during adaptive radiation...

..This effect seems relatively unimportant for our system because genetic divergence and gene flow were not correlated with ecologically relevant habitat features of lakes (surface area) or streams (width, depth, flow, canopy openness)...

..Because reproductive trade-offs should be almost universal and selection acting on them should typically vary in time and space, the mechanism described herein may explain much of the natural variation in senescence...

..Our results suggest that natural selection promotes the adaptive divergence of lake and stream stickleback. but that the magnitude of divergence can be constrained by gene flow...

..Based on these observations, we advance a hypothesis for why populations adapting to different environments should show adaptive genetic divergence in morphology-performance mapping...

..We discuss the implications of our work for the study of factors influencing the evolution of species' ranges...

..e., only 14-20% of the expected morphological divergence in the absence of gene flow was observed). Such approaches may be useful in other taxa to estimate how important gene flow is in constraining adaptive divergence in nature...

..quot; We also show how single-generation pedigrees, and even simple marker-based regression methods, can provide accurate estimates of quantitative genetic parameters in at least some natural systems...

..Our study thus confirms that mechanisms of adaptive speciation are not necessarily mutually exclusive and uncovers the complex ecology-geography interactions that underlie the evolution of mating isolation in nature...

..These results are consistent with the hypothesis that the rugged adaptive landscapes promoting and maintaining diversification in nature can be smoothed by human activities, thus hindering ongoing adaptive radiation...

..Our results suggest that parallel evolution, and deviations from it, are primarily the result of natural selection, which corresponds in only some respects to the dichotomous habitat classifications frequently used in such studies...

..These findings provide insights into the strengths and weaknesses of using neutral markers to infer ecological speciation in natural systems...

..In contrast, differences in predation did appear to reduce contemporary dispersal. We suggest that the standard predictions of ecological speciation may be heavily nuanced by the mating behaviour and life history strategies of guppies...

..Patterns of genetic similarity within and between species also suggest that interspecific hybridization might contribute to the formation of beak-size morphs within G. fortis...

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..Our study thus also reveals the value of simultaneously testing multiple environmental factors that may drive tertiary sex ratio variation...

..Our inability to find indirect genetic benefits of polyandry despite detailed pedigree and survival information suggests the need for similar assessments in other natural populations...

..Our results support those of some other recent studies in suggesting that bigger/fatter/faster is not always better, and may often be worse...

..At the same time, they reveal several interesting nonlinearities in interactions between environmental differences, sexual preference, dispersal and population size...

..stream) with quantitative estimates of selective forces and information on trait (co)variances...

..platei. Finally, pristine, high-order lakes should be actively protected as these have become rare and irreplaceable unspoiled references of the most diverse, natural lake ecosystems in Patagonia...

..e. body size and growth) among sites. The finding of at least some site fidelity in females also supports the need for careful conservation of each nursery...

..The theoretical framework we outline should provide an improved basis for future empirical tests of the role of population mixing in adaptive divergence...

..We suggest that the parallel evolution of male signalling traits may sometimes first require the parallel evolution of female preferences...

..Improvements in empirical approaches promise to eventually allow general inferences about the relative strength of different causal interactions during adaptive diversification...

..We also document restrictions on gene flow between the morphs, as revealed by genetic variation at 10 microsatellite loci. Our results provide strong support for the central role of ecology during the early stages of adaptive radiation...

..In particular, we encourage further research to disentangle the relative importance of adaptive and nonadaptive variation in senescence...

..This may help to explain the positive correlation between adult body size and egg size observed in fishes that cluster their eggs...