Too Hot to Eat: Wild and Lab-Bred Lymnaea stagnalis Differ in Feeding Response Following Repeated Heat Exposure

Acute extreme heat events are increasing in frequency and intensity. Understanding their effects on ectothermic organisms' homeostasis is both important and urgent. In this study we found that the exposure to an acute heat shock (30 degrees C for 1 hour) repeated for a seven-day period severely suppressed the feeding behavior of laboratory-inbred (W-strain) Lymnaea stagnalis, whereas the first-generation offspring of freshly collected wild (F-1 D-strain) snails raised and maintained under similar laboratory conditions did not show any alterations. The W-strain snails might have inadvertently been selected against heat tolerance since they were first brought into the laboratory many (similar to 70) years ago. We also posit that the F-1 D-strain snails do not perceive the heat shock as a sufficient stressor to alter their feeding response because their parental populations in wild environments have repeatedly experienced temperature fluctuations, thus becoming more tolerant and resilient to heat. The different responses exhibited by two strains of the same species highlight the importance of selecting the most appropriate strain for addressing questions about the impacts of global warming on organisms' physiology and behavior.

Automated summary

This study found that laboratory-reared snails showed a severe suppression in feeding behavior when exposed to a seven-day period of acute heat shock, while wild snails raised in similar laboratory conditions did not show any changes. The different responses might be due to inadvertent selection against heat tolerance in laboratory-reared snails and the wild snails' increased tolerance and resilience to heat.