Cold Blooded Animals: Metabolism & Efficiency

[at2341]

Hi,

Cold blooded animals don't produce body heat to keep themselves warm. Why is this?

Is their metabolism more efficient (produce more ATP rather than heat)?

 

[mgb_phys]

It's an evolutionary trade off.
Cold blooded - you don't waste energy keeping warm so you don't have to run around chasing food all the time, but you pay for it in not being able to move as fast for as long.
Warm blooded - you can be much more active and are able to live in a wider range of climates - but you have to be active to chase food all the time!

Interestingly warm blooded animals can be simpler form a chemical/genome sense - since ou are always at one temperate you only need one mechanism for making each chemical you need, col blooded animals have a much more complicated task to mak the same chemical by many different pathways at diffeent temperatures.
This is one of those cases where a simpliication has evolved.

 

[at2341]

THanks for the reply

You say that cold blooded animals "can't move as fast" while warm blooded animals move faster.

I thought:
cold blooded = less heat = more ATP = more energy to move
warm = more heat = less ATP = less energy to move

Is what you said about cold blooded animals not moving as fast not related to energetic efficiency?

 

[mgb_phys]

Generally slow blooded animals can't sustain movement for as long - crocodiles are pretty dangerous for the first minute but aren't going to win any marathons.
Sorry not an expert on their biochemistry.

 

[binzing]

Ever seen ants on a cool or cold day? They don't move fast.

 

[sas3]

Some plants also produce heat.

http://www.sciencenews.org/articles/20031213/bob9.asp