Freeze avoidance in a mammal: body temperatures below 0¦ C in an arctic hibernator
Barnes BM. 1989. Freeze avoidance in a mammal: body temperatures below 0¦ C in an arctic hibernator. Science. 244(4912):593-1595
Hibernating arctic ground squirrels, Spermophilus parryii, were able to adopt and spontaneously arouse from core body temperatures as low as -2.9 degrees C without freezing. Abdominal body temperatures of ground squirrels hibernating in outdoor burrows were recorded with temperature-sensitive radiotransmitter implants. Body temperatures and soil temperatures at hibernaculum depth reached average minima during Februrary of -1.9 degrees and -6 degrees C, respectively. Laboratory-housed ground squirrels hibernating in ambient temperatures of -4.3 degrees C maintained above 0 degrees C thoracic temperatures but decreased colonic temperatures to as low at --1.3 degrees C. Plasma sampled from animals with below 0 degree C body temperatures had normal solute concentrations and showed no evidence of containing antifreeze moleclues.
- Type
- Journal Article
- Authors
- Barnes, B
- Units
- ARCN , BELA , CAKR , GAAR , KOVA , NOAT
- Keywords
- Arctic, Toolik, Wildlife