Biology: Concepts and Investigations 2nd Edition by Mariëlle Hoefnagels

Exercise 2

Birds and mammals are endotherms: they maintain a constant internal body temperature no matter whether the environment is cold or hot (within limits, of course). An endotherm that gets too cold will increase its metabolic rate to generate heat. An ectothermic animal such as a reptile, on the other hand, allows its body temperature to fluctuate with the environment. If you own a pet rat and a pet snake of equal weight, which will require more food and why?