To use or not to use torpor? Activity and body temperature as predictors

@article{Christian2007ToUO,
  title={To use or not to use torpor? Activity and body temperature as predictors},
  author={Nereda Geraldine Christian and Fritz Geiser},
  journal={Naturwissenschaften},
  year={2007},
  volume={94},
  pages={483-487}
}
When food is limited and/or environmental conditions are unfavourable, many mammals reduce activity and use torpor to save energy. Nevertheless, reliable predictors for torpor occurrence, especially in the wild, are currently not available. Interrelations between torpor use and other energy conserving strategies are also poorly understood. We tested the hypothesis that reductions in normothermic body temperature (Tb) and the period of activity before torpor events could be used as predictors… 
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