Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Cold blooded animals

  1. Feb 7, 2008 #1

    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)?
  2. jcsd
  3. Feb 7, 2008 #2


    User Avatar
    Science Advisor
    Homework Helper

    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.
  4. Feb 8, 2008 #3
    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?
  5. Feb 8, 2008 #4


    User Avatar
    Science Advisor
    Homework Helper

    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.
  6. Feb 8, 2008 #5
    Ever seen ants on a cool or cold day? They don't move fast.
  7. Feb 9, 2008 #6


    User Avatar
    Gold Member

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook