Summary
This paper presents the first report of a mammalian internal organ with a lower temperature than its abdominal surrounds. Heterocephalus glaber, the naked mole-rat, is a poikilothermic mammal that leads a strictly subterranean existence and consumes a high proportion of fibre in its diet. The fermentation chamber in these animals appears to absorb rather than generate heat and the temperature in it was consistently 1.2±0.5°C (n=17) lower than rectal temperature. A caecum with a lower temperature than its abdominal surrounds provides an internal heat sink which could be advantageous for metabolic heat dissipation in the plugged humid burrows in which the naked mole-rat permanently resides.
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Abbreviations
- RH:
-
relative humidity
- T b :
-
body temperature
- T c :
-
caecal temperature
- T i :
-
intraperitoneal temperature
- T r :
-
rectal temperature
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Yahav, S., Buffenstein, R. Caecal function provides the energy of fermentation without liberating heat in the poikilothermic mammal, Heterocephalus glaber . J Comp Physiol B 162, 216–218 (1992). https://doi.org/10.1007/BF00357526
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DOI: https://doi.org/10.1007/BF00357526