What is a cold blooded animal
A fish swimming in water at a temperature of 40°f will have a body temperature that is very close to 40 degrees fahrenheit.These animals change their environment to normalize their internal functions.A fish swimming in 40° f water will have a body temperature very near 40° f.Ectothermy, controlling body temperature through external processes, such as by basking in the sun poikilothermy, the ability of an organism to function over a wide internal temperature rangeThey can be found in warm, temperate waters in every ocean around the world, and have been evolving since the miocene era.
The same fish in 60° f water will have a body temperature near 60° f.The body temperature of such animals is approximately equal or a bit higher than that of the environment's temperature.Not doing so will reduce their body temperature drastically, and they won't be able to function.