scholarly journals Evaporative Cooling in the Desert Cicada: Thermal Efficiency and Water*sol;Metabolic Costs

1991 ◽  
Vol 159 (1) ◽  
pp. 269-283
Author(s):  
NEIL F. HADLEY ◽  
MICHAEL C. QUINLAN ◽  
MICHAEL L. KENNEDY
Keyword(s):  
Body Temperature ◽  
Gas Exchange ◽  
Water Loss ◽  
Thermal Efficiency ◽  
Evaporative Cooling ◽  
Water Flux ◽  
Simultaneous Measurements ◽  
Metabolic Costs ◽  
Hydration State

Using plant xylem water for evaporative cooling, the desert cicada Diceroprocta apache can maintain a body temperature as much as 5°C below ambient (Ta=42°C). Simultaneous measurements of water loss and gas exchange for cicadas feeding on perfused twigs show substantial increases in transpiration at temperatures at which evaporative cooling begins (between 37 and 38°C), but only modest increases in Vo2 and Vco2. The extent and duration of evaporative cooling depend on the cicada's hydration state and the rate of water flux from cuticular pores located on the surface of the thorax and abdomen.

scholarly journals Respiratory Strategies in Relation to Ecology and Behaviour in Three Diurnal Namib Desert Tenebrionid Beetles

Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1036
Author(s):  
Frances D. Duncan
Keyword(s):  
Gas Exchange ◽  
Water Loss ◽  
Evaporative Cooling ◽  
Respiratory Physiology ◽  
Metabolic Rates ◽  
Beetle Species ◽  
Water Droplets ◽  
Namib Desert ◽  
Flow Through

The respiratory physiology of three diurnal ultraxerophilous tenebrionid beetles inhabiting either the dune slipface or gravel plain in the Namib Desert was investigated. The role of the mesothoracic spiracles and subelytral cavity in gas exchange was determined by flow-through respirometry. All three species exhibited the discontinuous gas exchange cycles with a distinct convection based flutter period and similar mass specific metabolic rates. There was variation in their respiration mechanics that related to the ecology of the species. The largest beetle species, Onymacris plana, living on the dune slipface, has a leaky subelytral cavity and used all its spiracles for gas exchange. Thus, it could use evaporative cooling from its respiratory surface. This species is a fog harvester as well as able to replenish water through metabolising fats while running rapidly. The two smaller species inhabiting the gravel plains, Metriopus depressus and Zophosis amabilis, used the mesothoracic spiracles almost exclusively for gas exchange as well as increasing the proportional length of the flutter period to reduce respiratory water loss. Neither species have been reported to drink water droplets, and thus conserving respiratory water would allow them to be active longer.

scholarly journals Regional Differences in Cuticular Permeability in the Desert Cicada Diceroprocta Apache: Implications for Evaporative Cooling

1989 ◽  
Vol 141 (1) ◽  
pp. 219-230 ◽  
Author(s):  
NEIL F. HADLEY ◽  
ERIC C. TOOLSON ◽  
MICHAEL C. QUINLAN
Keyword(s):  
Body Temperature ◽  
Water Loss ◽  
Temperature Increase ◽  
Regional Differences ◽  
Water Flux ◽  
Dorsal Surface ◽  
Male And Female ◽  
Cuticular Permeability ◽  
Higher Temperature

The cuticular permeability of the desert cicada Diceroprocta apache was measured in vivo from three regions of the dorsal surface: (1) the midline of the thorax (= dorsal thorax), a region that contains large pores (7–8 μm in diameter) located in a central tract; (2) the lateral thorax, a region in which large pores are absent, and (3) the midline of the abdomen, a region in which large pores are uniformly distributed over the surface. Transcuticular water flux rates were similar for all three areas at 27.0°C; however, at 41.5°C rates increased sharply for the dorsal thorax and abdomen, with tracings showing numerous irregular peaks that represent cycles of water extrusion. Transcuticular water flux for the lateral thorax, in contrast, was relatively unaffected by the temperature increase and the tracings remained relatively flat. Death of the animal at the higher temperature resulted in a significant decrease in water loss rates and a loss of the cycling pattern in both the dorsal thorax and abdomen, whereas water loss through the lateral thorax did not change. The active extrusion of water begins at 39.2-39.3°Cin both male and female cicadas. Our findings confirm that the large pores are the routes by which water reaches the surface and that the temperature at which this active extrusion of water begins corresponds to the point where cicadas must seek milder microclimates to prevent body temperature from reaching lethal levels.

Heterothermy, torpor, respiratory gas exchange, water balance and the effect of feeding in Gould's long-eared bat Nyctophilus gouldi.

1994 ◽  
Vol 197 (1) ◽  
pp. 309-335
Author(s):  
S Morris ◽  
A L Curtin ◽  
M B Thompson
Keyword(s):  
Body Temperature ◽  
Gas Exchange ◽  
Nutritional Status ◽  
Metabolic Rate ◽  
Water Loss ◽  
Respiratory Exchange Ratio ◽  
Thermal Conductance ◽  
Evaporative Water ◽  
Effects Of Temperature ◽  
Effect Of Feeding

The effects of temperature and nutritional status on the metabolic rate of Nyctophilus gouldi were examined. Bats fed marked meals first defecated approximately 1.34 h after feeding and were calculated to have a mean retention time of 5.38 +/- 0.57 h but to be truly post-absorptive after 9 h. Over the temperature range 1-35 degrees C, the metabolic rate (Vo2) and body temperature (Tb) of fasted bats were extremely labile. Below 30 degrees C, the bats all entered torpor and between 10 and 15 degrees C showed a mean 84% reduction over the maximal Vo2. Body temperature was also minimal over this range (Tb = 12.5 degrees C, Ta = 10-15 degrees C). Both total and dry thermal conductance increased in a curvilinear manner with temperature, total conductance from 3.38 +/- 0.65 J g-1 h-1 degree C-1 at 1 degree C to 24.25 +/- 1.99 J g-1 h-1 degree C-1 at 35 degrees C (mean +/- S.E.M.), while the rate of evaporative water loss increased with Ta by a maximum of 10-fold from 0.21 mg g-1 h-1 at 5 degrees C to 2.69 mg g-1h-1 at 35 degrees C. Between 10 and 25 degrees C, intermittent respiration characterised by episodic bouts of breathing/gas exchange and periods of apnoea with no measurable Vo2 occurred. Although the duration of apnoea decreased when temperature was increased, the volume of oxygen taken up in each episode did not change. Mean respiratory exchange ratio (RER) was low (0.64-0.77) in post-absorptive bats, typical of fat utilisation, but during torpor ranged from near 0 to near 2, indicating discontinuous and disproportional gas exchange. Feeding produced a condition of relatively sustained homeothermy and high RER in the bats which persisted for 9 h, after which the N. gouldi became torpid. Immediately after feeding, the Vo2 of the bats increased fivefold above the post-absorptive level, while the Vco2 increased by more than eightfold. Similarly, body temperature also increased, declining to torpid values after 9. The RER in immediately post-feeding bats was near 1.0 but subsequently declined to near 0.7, indicating a switch from carbohydrate to fat utilisation. Therefore, the N. gouldi were heterothermic, exhibited a highly labile metabolic rate, and rates of heat and water loss, and Tb which were influenced both by ambient temperature and by nutritional status.

scholarly journals Chronicvs.Short-Term Acute O3Exposure Effects on Nocturnal Transpiration in Two Californian Oaks

2007 ◽  
Vol 7 ◽  
pp. 134-140 ◽  
Author(s):  
N. E. Grulke ◽  
E. Paoletti ◽  
R. L. Heath
Keyword(s):  
Gas Exchange ◽  
Water Loss ◽  
Exchange System ◽  
Short Term ◽  
Blue Oak ◽  
Unexposed Control ◽  
Nocturnal Transpiration ◽  
Gas Exchange System ◽  
Black Oak ◽  
Oak Seedlings

We tested the effect of daytime chronic moderate ozone (O3) exposure, short-term acute exposure, and both chronic and acute O3exposure combined on nocturnal transpiration in California black oak and blue oak seedlings. Chronic O3exposure (70 ppb for 8 h/day) was implemented in open-top chambers for either 1 month (California black oak) or 2 months (blue oak). Acute O3exposure (~1 h in duration during the day, 120–220 ppb) was implemented in a novel gas exchange system that supplied and maintained known O3concentrations to a leaf cuvette. When exposed to chronic daytime O3exposure, both oaks exhibited increased nocturnal transpiration (without concurrent O3exposure) relative to unexposed control leaves (1.8× and 1.6×, black and blue oak, respectively). Short-term acute and chronic O3exposure did not further increase nocturnal transpiration in either species. In blue oak previously unexposed to O3, short-term acute O3exposure significantly enhanced nocturnal transpiration (2.0×) relative to leaves unexposed to O3. California black oak was unresponsive to (only) short-term acute O3exposure. Daytime chronic and/or acute O3exposures can increase foliar water loss at night in deciduous oak seedlings.

Effects of Neem EC on gas exchange, tracheal ventilation, and water loss in diapausing pupae ofPieris brassicae

2008 ◽  
Vol 126 (2) ◽  
pp. 165-173 ◽  
Author(s):  
Katrin Jõgar ◽  
Aare Kuusik ◽  
Luule Metspalu ◽  
Külli Hiiesaar ◽  
Maria Grishakova ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Water Loss
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