Based on how the metabolic rates of ectotherms and endotherms respond to temperature, at which temperature would you expect the differences in metabolic rates between ectotherms and endotherms to be largest? (hint: think about the response curve of each type of animal to environmental temperature.)

For ectotherms, on the other hand, body temperature mainly depends on external heat sources. That is, ectotherm body temperature rises and falls along with the temperature of the surrounding environment. Although ectotherms do generate some metabolic heat—like all living things—ectotherms can't increase this heat production to maintain a specific internal temperature.