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ABSTRACT Climate change is threatening global biodiversity as a result of increasing temperature and climate variability outpacing adaptation rates. Ectothermic animals, such as most fishes, are particularly vulnerable to environmental change because their physiology is intimately controlled by their surrounding environment. Importantly, the impact of temperature on animals depends not only on the degree of warming but also on their ability to accurately detect and evade that warming. The first step in this process is the recognition of changes in temperature by integral membrane proteins such as transient receptor potential (TRP) channels, some of which are temperature sensitive (thermoTRPs). Most of our understanding of thermoTRPs comes from studies in mammals, with a dearth of information in ectotherms on thermal sensitivities, and modulation of these thermal sensors. In this Commentary, we highlight what is known about the mechanism of temperature sensing in fishes. We also propose that changes in biological context (e.g. social interactions, lipids and immune state), leading to changes in physiology and behaviour, influence how fish sense temperature, potentially altering thermal susceptibility. Finally, we discuss redundancy in temperature-sensing systems, identify knowledge gaps, and suggest integrative approaches and questions for us to better understand temperature sensing and its modulation in fishes.
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Diet effects on ectotherm thermal performance
ABSTRACT The environment is changing rapidly, and considerable research is aimed at understanding the capacity of organisms to respond. Changes in environmental temperature are particularly concerning as most animals are ectothermic, with temperature considered a key factor governing their ecology, biogeography, behaviour and physiology. The ability of ectotherms to persist in an increasingly warm, variable, and unpredictable future will depend on their nutritional status. Nutritional resources (e.g. food availability, quality, options) vary across space and time and in response to environmental change, but animals also have the capacity to alter how much they eat and what they eat, which may help them improve their performance under climate change. In this review, we discuss the state of knowledge in the intersection between animal nutrition and temperature. We take a mechanistic approach to describe nutrients (i.e. broad macronutrients, specific lipids, and micronutrients) that may impact thermal performance and discuss what is currently known about their role in ectotherm thermal plasticity, thermoregulatory behaviour, diet preference, and thermal tolerance. We finish by describing how this topic can inform ectotherm biogeography, behaviour, and aquaculture research.
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- Award ID(s):
- 2305704
- PAR ID:
- 10524136
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Biological Reviews
- Volume:
- 99
- Issue:
- 4
- ISSN:
- 1464-7931
- Page Range / eLocation ID:
- 1537 to 1555
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/brv.13081
