they can walk or they can use their webs like spiders to move through the air...=]
Aerodynamic
how electron move in vacuum and not move in air
joy
you fly
Air
An eagle uses its wings to move and fly as most birds do. The wings move up and down in order for air to flow through them and allow the eagle to move forward through the air.
sound waves can not travel through space since they use the air around us to move.
streamlined
fly
Airplanes move through the air in a similar fashion to the way boats move through the water.
warm air