Hollow, light bones. Big chest muscles.
It is not only birds that fly. Bats fly and they are not birds.
Many species of birds learn how to fly, but they are built for it. Butterflies learn how to fly, but they are built for it. What about a housefly? It seems to be an internal trait that needs some learning to perfect.
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.
Most birds can fly. Not all.
The birds that can fly because it is easier for them to find food.
all birds fly xept penguins
When the Birds Fly South was created in 1945.
Birds Fly South was created in 2001.
Birds do not fly all the way to the southern hemisphere, they fly to the equator.
maybe but how birds fly birds fly by using there wings becuse feather make the birds fly bye love u by your boyfreaind or girlfreaind
The nest was built by birds.
birds fly in the troposphere which is the lowest layer of the atmosphere.