Heat tolerance and its evolutionary potential along a latitudinal gradient in Daphnia magna
Year: 2014
Type: article
Abstract: © 2014 Aurora N. Geerts. Background: Extreme weather events follow latitudinal patterns and are increasing due to climate change. To persist, natural populations must adapt to the increased occurrence of heat waves. Hypothesis: Heat tolerance is higher at lower latitudes and in smaller animals. Animals show evolutionary potential for heat tolerance. Organism: The water flea, Daphnia magna, a common species in bodies of fresh water. Methods: Set up a common-garden experiment using six populations spread across three latitudes in Western Europe, thereby creating a latitudinal gradient in local temperatures. Measure CTmax, the temperature above which animals lose motor function. Results: Thermal tolerance increased with increasing local temperatures. Body size, which was smaller at the southern latitude, negatively affected heat tolerance. Heat tolerance showed genetic variation within latitudes. Conclusions: Daphnia magna possesses the evolutionary potential to increase its heat tolerance if temperatures warm. Its heat tolerance shows latitudinal adaptation to local temperatures. A parallel pattern in body size magnifies the latitudinal pattern in heat tolerance.
Source: Lirias
Authors: Aurora Geerts, Luc De Meester, Robby Stoks
Institution: KU Leuven
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
Funders: KU Leuven, Vlaamse regering
Award: G1418014755
OpenAlex ID: W1445034711