Seasonality of torpor and thermoregulation in three dasyurid marsupials

@article{Geiser2004SeasonalityOT,
  title={Seasonality of torpor and thermoregulation in three dasyurid marsupials},
  author={Fritz Geiser and R. V. Baudinette},
  journal={Journal of Comparative Physiology B},
  year={2004},
  volume={157},
  pages={335-344}
}
SummarySeasonal variation in the pattern of torpor and temperature regulation was investigated in the closely related arid zone dasyurid marsupialsSminthopsis crassicaudata (17 g),S. macroura (24 g), andDasyuroides byrnei (120 g). The tendency to enter torpor was greater, torpor commenced earlier, torpor duration was longer, and body temperatures (Tb) were lower inSminthopsis spp. than inD. byrnei. The minimum mass-specific rate of oxygen consumption ( $$\dot V_{O_2 } $$ ) of torpid animals was… 
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    Oecologia
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References

SHOWING 1-10 OF 37 REFERENCES
Thermoregulation and torpor in the Kultarr,Antechinomys laniger (Marsupialia: Dasyuridae)
  • F. Geiser
  • Biology
    Journal of Comparative Physiology B
  • 2004
TLDR
The lowest relative weight loss was observed at theTa of the longest torpor bouts and lowest metabolism during torpor, which was parallel to theTa related increased in metabolism of normothermic resting, active, and arousing animals.
The influence of temperature and photophase on daily torpor inSminthopsis macroura (Dasyuridae: Marsupialia)
TLDR
An eight hour phase shift of the dark-light cycle resulted in a corresponding shift in the diurnal torpor-activity cycle and it appears that light is an important cue for the timing of daily torpor.
Shifts of thermogenesis in the prairie vole (Microtus ochrogaster)
TLDR
Arguments are presented suggesting that prairie voles compensate for increased weight-specific thermogenesis in winter by lowering body weight, implying different sorts of metabolic organization.
Seasonal control of energy requirements for thermoregulation in the djungarian hamster (Phodopus sungorus), living in natural photoperiod
TLDR
All seasonal changes were similar inPhodopus living inside or outside, suggesting that seasonal changes in photoperiod and not seasonalChanges inTa is the overriding controller for the environmental cueing of seasonality in energy requirements for thermoregulation.
Seasonal changes in the critical arousal temperature of the marsupialSminthopsis crassicaudata correlate with the thermal transition in mitochondrial respiration
TLDR
During periods of torporSminthopsis crassicaudata, a dasyurid marsupial, regulated its body temperature above about 16.3°C in summer and 13.0% in winter, and the lowest regulated body temperature was just above the temperature where changes were detected in mitochondrial respiration.
Suppression of Metabolism during Hibernation in Ground Squirrels (Citellus lateralis)
TLDR
Data from 11 ground squirrels indicate that respiratory acidosis occurs during hibernation but that its role may be limited to suppression of thermoregulatory thermogenesis and not suppression of metabolism below basal levels.
From Ectothermy to Heterothermy: The Energetics of the Kowari, Dasyuroides byrnei (Marsupialia: Dasyuridae)
TLDR
Rates of cooling and oxygen consumption indicate that independent thermoregulation (euthermia) was achieved in the kowari, Dasyuroides byrnei, and the development of endothermy was accompanied by the ability to enter torpor.
Torpor and Nest-Sharing in Free-Living Sminthopsis crassicaudata (Marsupialia) and Mus musculus (Rodentia)
TLDR
A field study of the coexisting, nocturnally active small mammals Sminthopsis crassicaudata and Mus musculus showed that both species occupied nests during the day in groups of up to nine individuals, with nest-sharing common in winter but declined during the breeding period of spring and summer.
Bioenergetics and body size in dasyurid marsupials
MACMILLEN, RICHARD E., AND TOHN E:. NELSON. Bioenergetics and body size in dusyurid marsupials. Am. j. Physiol. 2 17(4) : 1246-l 251. 1969.-Basal. metabolic rate, weight-specific conductance, and
Seasonal Study of Spontaneous Daily Torpor in the White-Footed Mouse, Peromyscus leucopus
TLDR
Daily torpor was observed in both mouse populations from mid-December through mid-February, and 96% of the animals in torpor were found in groups of two to six mice, and all mice in the nest box were usually torpid.
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