Mammals can run fast but generally birds seem better equipped at smaller and larger sizes to run faster. Have you ever noticed that even walking uphill, it's easier to walk backwards for less energy use.
Ostriches, roadrunners etc are incredibly fast
- Birds are better designedVote A
- Mammals are better designedVote B
- OtherVote C
Most Helpful Girl
I'm way too clumbsy to walk backwards... especially uphill! It wouldn't be pretty.0
Most Helpful Guy
Firstly, as someone else pointed out, they are actually using the same running motion as other bipeds - it's just that they effectively have an extra joint in their foot as well (it's most obvious if you look at that velociraptor).
Secondly, if you look at a fast quadruped such as a cheetah or greyhound, you'll see that they're making extensive use of their back muscles as well as all four limbs, which gives them more power and a much longer stride length. As a result, cheetahs are much, much faster than ostriches, and even a whippet is a little faster, in spite of being tiny in comparison.