Cold adaptation in geographical populations of Drosophila melanogaster: phenotypic plasticity is more important than genetic variability
Article first published online: 21 SEP 2004
Volume 18, Issue 5, pages 700–706, October 2004
How to Cite
AYRINHAC, A., DEBAT, V., GIBERT, P., KISTER, A.-G., LEGOUT, H., MORETEAU, B., VERGILINO, R. and DAVID, J. R. (2004), Cold adaptation in geographical populations of Drosophila melanogaster: phenotypic plasticity is more important than genetic variability. Functional Ecology, 18: 700–706. doi: 10.1111/j.0269-8463.2004.00904.x
- Issue published online: 21 SEP 2004
- Article first published online: 21 SEP 2004
- Received 15 January 2004; revised 30 March 2004; accepted 18 May 2004
- Chill coma;
- cold tolerance;
- latitudinal cline;
- reaction norms;
- recovery time
- 1According to their geographical distribution, most Drosophila species may be classified as either temperate or tropical, and this pattern is assumed to reflect differences in their thermal adaptation, especially in their cold tolerance. We investigated cold tolerance in a global collection of D. melanogaster by monitoring the time adults take to recover from chill coma after a treatment at 0 °C.
- 2Flies grown at an intermediate temperature (21 °C) showed a significant linear latitudinal cline: recovery was faster in populations living in colder climates.
- 3The role of growth temperature was analysed in a subset of tropical and temperate populations. In all cases, recovery time decreased when growth temperature was lowered, and linear reaction norms were observed. This adaptive phenotypic plasticity explained more than 80% of the total variation, while genetic latitudinal differences accounted for less than 4%.
- 4The beneficial effect observed in adults grown at a low temperature contrasts with other phenotypic effects which, like male sterility, appear as harmful and pathological. Our results point to the difficulty of finding a general interpretation to the diversity of plastic responses that are induced by growth temperature variations.