5 ms·

Reptiles need much less food than mammals.

• bryanlarsen 9y ago
  But birds need more food than mammals. And birds are a group of dinosaurs. Under some classification systems dinosaurs (including birds) are in the reptile tree, but in others they aren't.
  • mrfusion 9y ago
    Birds need more food? Where does it say that? Do they have a less efficient metabolism or digestion maybe?
    • Rexxar 9y ago
      They are smaller, have higher body temperature and use a more energy intensive way of moving. They're necessarily consume more food. It's probably reversed if you compare a small bat to ostriches, but it's true in general.
      • rmetzler 9y ago
        Bats aren't birds.
        • andrewl 9y ago
          Rexxar's point was about mechanisms of locomotion and body size. While we generally expect birds to have a faster metabolism than mammals because they're small and because flying takes so much energy, the reverse would probably be the case when comparing ostriches and bats. The ostrich is a 250-pound non-flying bird, and bats are very light flying mammals. In that case, we expect the mammal to have the higher metabolism. I've also wondered if non-flying birds defecate less often, and flying mammals more often. I always assumed that birds emptied out so frequently because it's important to keep your weight down if you're flying, and much less important if you're walking.
    • bluedino 9y ago
      Flying takes a ton of energy. Hummingbirds are an extreme example but they have the highest metabolism of any animal and can eat multiples of their body weight in food each day