They have hollow bones.
Birds have hollow bones, and that makes them light enough for their wings to lift them off the ground. Also they have wings and lots of feathers, and they are shaped to give the bird lift so it can fly.
They are light enough and have wings.
they are light weight and have wings.
Because of their wings that makes them fly longer than other birds
All birds that are light and have feathers and have a purpose to fly
Birds have hollow bones that make them lighter so they can fly more easily.
Birds bones are hollow. That is why they can fly, because they are so light because of their hollow bones. x)
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.
It makes them lighter and so it is easier to fly.
Yes, it makes them lighter so they are able to fly easier.
Chickens are first of all birds and in order to fly, birds need to be aerodynamic. Less winf resistance makes it easier to fly so having reproductive organs insinde makes sense.
It uses its curved wings. The whole of a bird's body structure makes it very light. It also loses its weight by pooing almost everytime. So it will be lighter and is able to fly more easily. Some birds' body structures are already too big and they cannot fly. Well the reason birds CAN fly is because they have hollow bones. There hollow bones makes them lighter. They also have a KEEL bone which is used to keep the bird upright so they don't fall over during flight. and pooing doesnt make any difference with the birds weight!!