Flies don't have perfectly straight vision. They have many eyes that contribute to their vision so they can't fly in a straight line.
It depends whether it's flying in a straight line or not !
kiwi is a bird which can't fly
Cooper's hawks can fly in a straight line up to 55 mph.
It is not only birds that fly. Bats fly and they are not birds.
have to take breaks because they have to sleep and eat.
If you were flying a straight line, you would fly over South Dakota, Nebraska, Kansas, and Oklahoma.
Not sure what you mean by that, but birds do fly.
Crows are tyoe of birds who fly in packs but they don't always fly in straight lines.
Any creature with eyes could see that birds can fly. It wasn't until our earliest ancestors developed the ability to think before anyone gave the matter any thought.
Most birds can fly. Not all.
To say that birds use wings and feathers to fly, so all birds can fly, would be false. Not all birds can fly. An ostrich is an example of a bird that cannot fly.