An Ectotherm is a "cold blooded animal" meaning its body temperature is dependant on the external environment. Factors such as sunlight and shelter would affect an ectotherm's temperature.This would consequently affect their behaviour. Examples of ecotherms include fish and reptiles. Ectotherms have a lower rate of metabolism than endotherms, as they have a lower rate of respiration, which would be one of the mechanisms used to generate heat in an Endotherm. Endotherms would be more suited to living in extreme conditions than ecotherms, as their external environment does not have a significant effect on the body temperature.