Name Two adaptations that allow birds to fly.

The bodies of birds are adapted for flying. Many of a bird's bones are less dense than human bones, which makes birds' bodies lightweight. Flying birds have large chest muscles that move the wings. Birds have feathers that help them fly.

imagine a line passing through the center of earth that goes through both the north pole and the south pole. this imaginary line is called an axis. earth spins around its axis, just as a top spins around its spindle. this spinning movement is called earth's rotation. at the same time that the earth spins on its axis, it also orbits, or revolves around the sun. this movement is called revolution.