Commonly known as “cold-blooded” animals, ectotherms do not produce heat through body metabolism. In order to regulate their temperature, they utilize natural phenomena in their environment. This iguana, for example, may sit in sunlight or on warm rocks to heat up their internal systems. When its temperature rises past comfort, it will seek shade to bring its temperature back down. Maintaining homeostasis via external stimuli is what classifies such organisms as ectothermic.