The Role of Energy Availability in Mammalian Hibernation: A Cost‐Benefit Approach

@article{Humphries2003TheRO,
  title={The Role of Energy Availability in Mammalian Hibernation: A Cost‐Benefit Approach},
  author={Murray M. Humphries and Donald W. Thomas and Donald L. Kramer},
  journal={Physiological and Biochemical Zoology},
  year={2003},
  volume={76},
  pages={165 - 179}
}
Hibernation is widely regarded as an adaptation to seasonal energy shortage, but the actual influence of energy availability on hibernation patterns is rarely considered. Here we review literature on the costs and benefits of torpor expression to examine the influence that energy may have on hibernation patterns. We first establish that the dichotomy between food‐ and fat‐storing hibernators coincides with differences in diet rather than body size and show that small or large species pursuing… 
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The unique manner in which hibernators are controlled during the annual cycle, especially lipid reserves, makes them valuable and promising models for research into the mechanisms underlying these processes in all mammals.
Body Mass and Tail Girth Predict Hibernation Expression in Captive Dwarf Lemurs
TLDR
Assessment of torpor expression in captive dwarf lemurs, primates that are obligate, seasonal, and tropical hibernators, suggests that individuals optimize rather than maximize torpor according to body mass.
Field evidence for a proximate role of food shortage in the regulation of hibernation and daily torpor: a review
TLDR
Evidence on the proximate role of food availability in heterothermy regulation by endotherms is reviewed, and alternative hypotheses that remain to be tested are emphasized.
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The results indicate that reduced torpor expression by hibernators can result from an absence of energetic necessity rather than a lack of physiological capability and suggest that even endotherms sequestered in a hibernaculum may benefit from maintaining an elevated body temperature whenever possible.
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