Thermal evolution ameliorates the long-term plastic effects of warming, temperature fluctuations and heat waves on predator-prey interaction strength

How thermal evolution may affect trophic interactions and its implications for trophic system stability remains unstudied. To advance insights in how global warming shapes trophic interactions, we need to consider besides increases in mean temperatures, also daily thermal fluctuations (DTF) and heat waves (HW), and how their effects are modulated by thermal evolution.

Using a common-garden approach we tested how each thermal factor affected predator metabolic rate and functional response parameters, and used these responses to predict long-term predator-prey interaction strength between larvae of the damselfly Ischnura elegans and the water flea Daphnia magna. By using high- and low-latitude predator populations with the latter being exposed to higher mean temperatures, higher DTF and more frequent HW, we assessed the potential impact of thermal evolution at the high latitude using a space-for-time substitution.

In line with thermal adaptation, growth rates were faster and handlin...