Powered flight has evolved only 4 times (birds, bats, pterosaurs, and insects)... Insects were
the first to evolve flight, approximately 350 million years ago. The developmental origin of the
insect wing remains in dispute, as does the purpose prior to true flight.  One suggestion is that
wings initially were used to catch the wind for small insects that live on the surface of the
water, while another is that they functioned in parachuting, then gliding, then flight for
originally arboreal insects.