Weight and wingsize! Flying birds have special wings for flying. It also depends on the shape of the wings. Some birds have lost the ability to fly because it is simply not a trait necessary for survival. The ostrich is a well-known flightless bird that instead is able to run very fast. Penguins also cannot fly but are adept swimmers; their modified wings are very good for swimming but useless for flight. There is also a flightless cormorant that lives in the Galapagos Islands; again, it is a good swimmer and because it does not face predation on its island that would eradicate non-flyers, has lost the ability to fly.
Some parrots cannot fly because feathers on their wings have been clipped to prevent them from flying away. The feathers will usually grow back, and eventually, the bird should be able to fly again.
Dogs cannot fly. Their bodies are too heavy and they do not have wings.
Bats are mammals and they are capable of flight.
Birds can fly. Problem in the question?
That question is wrong. They can't. In real life, they cannot fly, but fall, and it's not reccomended. In movies, the can fly sometimes, but it js fictionary.
u suck
Dogs do not fly unless they take a ride in an aircraft.
All dogs can fly, they just need to be taught how. If your dog can't fly you are a terrible owner.
Ummmm.. No.
dogs can fly like a bird but only to some particular area not for long distance .
Heroin?
they fly north
Computer animation.
dogs that fly
probably because they fly.
no its impossible but pigs can fly.....dot dot dot
Dog and cats can't fly but they can jump high.
Petkeeping with Marc Morrone - 2002 Dogs on the Fly was released on: USA: 4 October 2004