Before revision: Dormancy and freezing in ectotherms Because they cannot actively down-regulate their body temperature or metabolic rate, ectothermic animals (including fish, reptiles, and amphibians) cannot hibernate .
After revision: Dormancy and freezing in ectotherms Because they cannot actively down-regulate their body temperature or metabolic rate, ectothermic animals (including fish, reptiles, and amphibians) cannot engage in obligate or facultative hibernation .