Influence of temperature on evaporative water loss and cutaneous resistance to water vapour diffusion in the orange-thighed frog (Litoria xanthomera)
Data(s) |
01/01/2003
|
---|---|
Resumo |
We evaluated the effect of ambient temperatures between 25 and 43°C on the rate of evaporative water loss (EWL) in eight adult <i>Litoria xanthomera</i> (average body mass = 7.3 ± 0.6 g). Frogs were placed in a cylindrical chamber that permitted them to fully conceal their ventral surfaces using a water-conserving posture. Their EWL was 7.1 ± 0.7 mg g<sup>–1</sup> h<sup>–1 </sup>at 25°C and reached 28.0 ± 2.5 mg g<sup>–1</sup> h<sup>–1</sup> at 43°C. Agar replicas of the frogs were used to evaluate boundary-layer resistances associated with the EWL measurements and, thus, to permit evaluation of cutaneous resistance to vapour diffusion (r<sub>c</sub>) in live frogs. The r<sub>c</sub> of <i>L. xanthomera</i> was stable over the temperature range of 25–35°C, averaging about 28 s cm<sup>–1</sup>, and then declined stepwise with ambient temperatures above 37°C. The highest r<sub>c</sub> recorded for each individual over the range of temperatures studied averaged 32.0 ± 1.2 s cm<sup>–1</sup>. The thermolabile nature of r<sub>c</sub> demonstrates a well developed thermoregulatory control of EWL in this species, a trait very similar in pattern and extent to that previously measured in the closely related <i>Litoria chloris</i>. <br /> |
Identificador | |
Idioma(s) |
eng |
Publicador |
CSIRO Publishing |
Relação |
http://dx.doi.org/10.1071/ZO02057 |
Direitos |
2003, CSIRO |
Tipo |
Journal Article |