Hybridization among related species is now recognized as common but it remains unclear how hybrid zones persist for prolonged periods. Here, we test the hypothesis that selection in different components of the life cycle may stabilize a hybrid zone. A hybrid zone occurs in southwest England between the marine mussels and .
View Article and Find Full Text PDFAt a proximal level, the physiological impacts of global climate change on ectothermic organisms are manifest as changes in body temperatures. Especially for plants and animals exposed to direct solar radiation, body temperatures can be substantially different from air temperatures. We deployed biomimetic sensors that approximate the thermal characteristics of intertidal mussels at 71 sites worldwide, from 1998-present.
View Article and Find Full Text PDFThis study examines the importance of thermal refugia along the majority of the geographical range of a key intertidal species (Patella vulgata Linnaeus, 1758) on the Atlantic coast of Europe. We asked whether differences between sun-exposed and shaded microhabitats were responsible for differences in physiological stress and ecological performance and examined the availability of refugia near equatorial range limits. Thermal differences between sun-exposed and shaded microhabitats are consistently associated with differences in physiological performance, and the frequency of occurrence of high temperatures is most probably limiting the maximum population densities supported at any given place.
View Article and Find Full Text PDFModeling the biogeographic consequences of climate change requires confidence in model predictions under novel conditions. However, models often fail when extended to new locales, and such instances have been used as evidence of a change in physiological tolerance, that is, a fundamental niche shift. We explore an alternative explanation and propose a method for predicting the likelihood of failure based on physiological performance curves and environmental variance in the original and new environments.
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