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Naturwissenschaften

, Volume 97, Issue 6, pp 601–605 | Cite as

Coping with chaos: unpredictable food supplies intensify torpor use in an arid-zone marsupial, the fat-tailed dunnart (Sminthopsis crassicaudata)

  • Adam J. MunnEmail author
  • Pippa Kern
  • Bronwyn M. McAllan
Short Communication

Abstract

The severity, duration and amplitude of extreme weather events are forecast to intensify with current climate trends, over both long (e.g. seasonal) and short (e.g. daily) time-scales. As such, the predictability of food supplies for many small endotherms is likely to become increasingly important. Numerous small mammals and birds combat food shortages using torpor, a controlled reduction in metabolic rate and body temperature that helps lower their daily energy requirements. As such, torpor often has been cited as a key feature allowing some small endotherms to survive highly unpredictable climates, such as tropics or dry deserts, but mensurative demonstrations of this are lacking. We have shown here that when a small desert marsupial, the fat-tailed dunnart (Sminthopsis crassicaudata), is offered unpredictable levels of daily food, they increase frequency of daily torpor and length of bouts compared with animals offered ad libitum food, but this was not found for animals offered a 70% food-restricted diet. Our data suggest that simple food restriction may not be sufficient for evaluating the efficacy of torpor as a strategy for managing unpredictable climates.

Keywords

Torpor Fat-tailed dunnart Unpredictability Energy restriction Food availability 

Notes

Acknowledgements

The experiments were carried out with permission from the Animal Ethics Committee of the University of Sydney (approval number: K22/1-2009/1/4931) and fully comply with the guidelines for the ethical experimentation on animals. This research was conducted under NSW National Parks and Wildlife Licence S10187. Thanks to Professor Fritz Geiser for the loan of numerous iButtons.

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Adam J. Munn
    • 1
    • 2
    Email author
  • Pippa Kern
    • 1
  • Bronwyn M. McAllan
    • 3
  1. 1.Faculty of Veterinary ScienceThe University of SydneySydneyAustralia
  2. 2.School of Biological SciencesThe University of WollongongWollongongAustralia
  3. 3.Discipline of Physiology School of Medical Sciences, and Bosch InstituteThe University of SydneySydneyAustralia

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