Torpor and basking in a small arid zone marsupial

@article{Warnecke2007TorporAB,
  title={Torpor and basking in a small arid zone marsupial},
  author={Lisa Warnecke and James M. Turner and Fritz Geiser},
  journal={Naturwissenschaften},
  year={2007},
  volume={95},
  pages={73-78}
}
The high energetic cost associated with endothermic rewarming from torpor is widely seen as a major disadvantage of torpor. We tested the hypothesis that small arid zone marsupials, which have limited access to energy in the form of food but ample access to solar radiation, employ basking to facilitate arousal from torpor and reduce the costs of rewarming. We investigated torpor patterns and basking behaviour in free-ranging fat-tailed dunnarts Sminthopsis crassicaudata (10 g) in autumn and… 
Basking and torpor in a rock-dwelling desert marsupial: survival strategies in a resource-poor environment
TLDR
This study suggests that by frequently employing daily torpor and basking and by appropriately coordinating their thermal biology with that of specific locations in their environment, Pseudantechinus can reduce daily energy expenditure and thus can live and reproduce in a challenging environment.
The role of basking in the development of endothermy and torpor in a marsupial
TLDR
Results from this study suggest that basking is a crucial behavioural trait that permits young marsupials and perhaps other juvenile altricial mammals to overcome the developmental stage between poikilothermy early in development and full endothermy later in life.
The energetics of basking behaviour and torpor in a small marsupial exposed to simulated natural conditions
TLDR
It is demonstrated, for the first time in the laboratory, that torpid animals actively move to a heat source to bask, and that this behaviour results in considerable energy savings, which supports the view that basking during normothermia and rewarming from torpor substantially reduces energetic requirements.
Activity and torpor in two sympatric Australian desert marsupials
TLDR
This study suggests that in winter, the smaller dunnarts can remain active only during the warmer first half of the night and energy-saving torpor becomes part of their daily routine, while the larger kowaries are less affected by cold winter nights and can maintain high night-time activity levels and commence reproduction already in winter.
The key to winter survival: daily torpor in a small arid-zone marsupial
TLDR
This study shows that for wild stripe-faced dunnarts daily torpor is an essential mechanism for overcoming energetic challenges during winter and that torpor data obtained in the laboratory can substantially underestimate the ecological significance ofdaily torpor in the wild.
Thermal biology, torpor use and activity patterns of a small diurnal marsupial from a tropical desert: sexual differences
TLDR
It is proposed that physiological as well as behavioural preparations for the September mating season that culminate in a complete male die-off might already impose energetic costs on males during winter.
Fat and fed: frequent use of summer torpor in a subtropical bat
TLDR
It is provided the first evidence that use of torpor in a free-ranging subtropical mammal is positively related with high body condition index, suggesting that employment of torpora is maximised and foraging minimised not because of food shortages or low energy stores but likely to avoid predation when bats are not required to feed.
Thermal Biology, Torpor, and Activity in Free‐Living Mulgaras in Arid Zone Australia during the Winter Reproductive Season
TLDR
In a resource‐poor environment during the least productive part of the year, frequent torpor seems to provide the means to compensate for the increased energetic costs associated with reproduction.
Some like it cold: summer torpor by freetail bats in the Australian arid zone
TLDR
It is demonstrated that this desert bat uses torpor extensively in summer and often rewarms passively from torpor to maximise energy and water conservation.
Torpor and basking after a severe wildfire: mammalian survival strategies in a scorched landscape
TLDR
The data suggest that torpor and basking are used by this terrestrial mammal to reduce energy and foraging requirements, which is important in a landscape where food and shelter are limited and predation pressure typically is increased.
...
...

References

SHOWING 1-10 OF 33 REFERENCES
The energetic cost of arousal from torpor in the marsupial Sminthopsis macroura : benefits of summer ambient temperature cycles
TLDR
The total cost of all three phases of torpor (entry, maintenance and arousal) was almost halved when animals were exposed to an ambient heating cycle from 15 °C to 25‬C over a 24-h period, and may represent an important energetic aid to free-ranging animals.
Seasonality of torpor and thermoregulation in three dasyurid marsupials
TLDR
The results suggest that seasonal changes in the pattern of thermoregulation and torpor in small dasyurids may be more distinct than in larger species.
Energetic Significance of Torpor and Other Energy-Conserving Mechanisms in Free-Living Sminthopsis-Crassicaudata (Marsupialia, Dasyuridae)
TLDR
Various energy-conserving mechanisms were used, even in the absence of short-term energetic problems, resulting in spontaneous energy savings and a reduced depletion of food.
The role of torpor in the life of Australian arid zone mammals.
TLDR
It appears that the success of small insectivorous/nectarivorous mammals and perhaps rodents in the Australian arid zone is partially due to their use of torpor, which appears to prolong life span.
Life in the Cold
TLDR
It is proposed that when well fed animals hibernate in comparatively mild climates, with food available, they are using the winter cold as a resource and "putting themselves on ice" until the next breeding season, which means echidnas are hibernating in mild climates for energy advantage, not from energetic necessity.
Influence of torpor on daily energy expenditure of the dasyurid marsupial Sminthopsis crassicaudata.
Exogenous passive heating during torpor arousal in free-ranging rock elephant shrews, Elephantulus myurus
Abstract. In the laboratory rock elephant shrews (Elephantulus myurus; mean body mass 56.6 g) displayed the lowest torpor Tb min yet recorded (ca. 5°C) in a placental daily heterotherm. It was
Was basking important in the evolution of mammalian endothermy?
TLDR
These findings provide the first evidence of basking during rewarming from torpor in mammals and may provide an alternative explanation as to how ancestral mammals could have become nocturnal to avoid diurnal predators despite their small size and a low endogenous heat production.
Nocturnal hypometabolism as an overwintering strategy of red deer (Cervus elaphus).
TLDR
Red deer, similar to many other northern ungulates, show large seasonal fluctuations of metabolic rate, as indicated by heart rate, with a 60% reduction at the winter nadir compared with the summer peak, suggesting that reducing endogenous heat production is not restricted to hibernators and daily heterotherms but is a common and well-regulated physiological response of endothermic organisms to energetically challenging situations.
Ecological, Physiological, and Biochemical Aspects of Torpor in Mammals and Birds
TLDR
This work has shown that torpor in birds and mammals is polyphyletic, and represents an advanced form of thermoregulation rather than a reversion to primitive poikilothermy, and is also being deployed by those which inhabit the subtropical and tropical climates.
...
...