Increased Thermal Sensitivity of a Tropical Marine Gastropod Under Combined CO2 and Temperature Stress

The ability of an organism to alter its physiology in response environmental conditions offers a short-term defense mechanism the face weather extremes resulting from climate change. These often manifest as multiple, interacting drivers, especially pH and temperature. In particular, decreased can impose constraints on biological mechanisms which define thermal limits by throwing off energetic equilibrium diminishing physiological functions (e.g., many marine ectotherms). For species, however, we do not have detailed understanding these interactive effects, acclimation responses. Here, investigated metabolic plasticity tropical subtidal gastropod ( Trochus maculatus ) increased levels CO 2 (700 ppm) heating (+3°C), measuring performance Q 10 coefficient) sensitivity [temperature maximum rate (T MMR ), upper lethal temperature (ULT)]. Individuals demonstrated stressors, with T increasing +4.1°C under higher temperatures, +2.7°C elevated , +4.4°C combined stressors. contrast, ULT only marginally (+0.3°C), but −2.3°C −8.7°C Therefore, although phenotypic is evident acclimation, acute seem be less flexible during acclimation.