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ABSTRACT Species' distributions are changing around the planet as a result of global climate change. Most research has focused on shifts in mean climate conditions, leaving the effects of increased environmental variability comparatively underexplored. This paper proposes two new macroecological hypotheses—thevariability damping hypothesisand thevariability adaptation hypothesis—to understand how ecological dynamics and evolutionary history could influence biogeographic patterns being forced by contemporary large‐scale climate change across all major ecosystems. The variability damping hypothesis predicts that distributions of species living in deep water environments will be least affected by increasing climate‐driven temperature variability compared with species in nearshore, intertidal and terrestrial environments. The variability adaptation hypothesis predicts the opposite. Where available, we discuss how the existing evidence aligns with these hypotheses and propose ways in which they may be empirically tested.
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Ecological change in dynamic environments: Accounting for temporal environmental variability in studies of ocean change biology
Abstract The environmental conditions in the ocean have long been considered relatively more stable through time compared to the conditions on land. Advances in sensing technologies, however, are increasingly revealing substantial fluctuations in abiotic factors over ecologically and evolutionarily relevant timescales in the ocean, leading to a growing recognition of the dynamism of the marine environment as well as new questions about how this dynamism may influence species' vulnerability to global environmental change. In some instances, the diurnal or seasonal variability in major environmental change drivers, such as temperature, pH and seawater carbonate chemistry, and dissolved oxygen, can exceed the changes expected with continued anthropogenic global change. While ocean global change biologists have begun to experimentally test how variability in environmental conditions mediates species' responses to changes in the mean, the extensive literature on species' adaptations to temporal variability in their environment and the implications of this variability for their evolutionary responses has not been well integrated into the field. Here, we review the physiological mechanisms underlying species' responses to changes in temperature,pCO2/pH (and other carbonate parameters), and dissolved oxygen, and discuss what is known about behavioral, plastic, and evolutionary strategies for dealing with variable environments. In addition, we discuss how exposure to variability may influence species' responses to changes in the mean conditions and highlight key research needs for ocean global change biology.
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- Award ID(s):
- 1752600
- PAR ID:
- 10363388
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Change Biology
- Volume:
- 26
- Issue:
- 1
- ISSN:
- 1354-1013
- Format(s):
- Medium: X Size: p. 54-67
- Size(s):
- p. 54-67
- Sponsoring Org:
- National Science Foundation
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