Critical thermal limits depend on methodological context

Date
2007
Authors
Terblanche, John S.
Deere, Jacques A.
Clusella-Trullas, Susana
Janion, Charlene
Chown, Steven L.
Journal Title
Journal ISSN
Volume Title
Publisher
Royal Society of Publishing
Abstract
A full-factorial study of the effects of rates of temperature change and start temperatures was undertaken for both upper and lower critical thermal limits (CTLs) using the tsetse fly, Glossina pallidipes. Results show that rates of temperature change and start temperatures have highly significant effects on CTLs, although the duration of the experiment also has a major effect. Contrary to a widely held expectation, slower rates of temperature change (i.e. longer experimental duration) resulted in poorer thermal tolerance at both high and low temperatures. Thus, across treatments, a negative relationship existed between duration and upper CTL while a positive relationship existed between duration and lower CTL. Most importantly, for predicting tsetse distribution, G. pallidipes suffer loss of function at less severe temperatures under the most ecologically relevant experimental conditions for upper (0.06°C min -1; 35°C start temperature) and lower CTL (0.06°C min -1; 24°C start temperature). This suggests that the functional thermal range of G. pallidipes in the wild may be much narrower than previously suspected, approximately 20-40°C, and highlights their sensitivity to even moderate temperature variation. These effects are explained by limited plasticity of CTLs in this species over short time scales. The results of the present study have broad implications for understanding temperature tolerance in these and other terrestrial arthropods. © 2007 The Royal Society.
Description
The original publication is available at http://rspb.royalsocietypublishing.org/
Keywords
Body temperature regulation, Tsetse Flies (Glossina pallidipes), Critical thermal limits (CTLs), Glossina (genus) -- Temperature tolerance
Citation
Terblanche, J. S.et al. 2007. Critical thermal limits depend on methodological context. Proceedings of the Royal Society B: Biological Sciences, 274(1628):2935-2942, doi:10.1098/rspb.2007.0985.