Can you explain why ectotherms cannot maintain their body temperature even though they seem to digest food through the same processes? Or am I wrong about that? Thank you

zoologicallyobsessed:

Animals that are exothermic regulate their body heat using behavioural means and therefore are dependent on external sources of heat. Unlike endothermic organisms that regulate their internal body temperature through chemical reactions and therefore are able to maintain a constant body temperature despite the environmental temperature. 

I think you’re a little confused because this process has really nothing to do with digesting certain types of food…. sure endothermic animals tend to have a higher rate of metabolism and therefore need to consume more sugars and fats, but it really doesn’t have much to do with digestion…. 

I have what I think is about the same question. 

According to every biology class I’ve taken so far, some of the heat in an endothermic organism is, essentially, wasted energy. It’s energy that escapes the various biological processes. 

The question is, why don’t reptiles do the same? Shouldn’t they have some sort of heat escaping from the same processes? Or do they have the same heat loss, but on a much smaller scale due to a slower metabolism?