Various reptiles have developed the ability to glide, but the pterosaurs were the only ones to develop true flight. The arms of a pterosaur were quite short, and its entire wing was supported by an enormously long fourth finger, leaving the other fingers free to function as a hand. A thin, skin-like membrane was stretched from the elongated finger to the sides of the body, and sometimes to the hind legs.

                             The whole body of the pterosaur was extremely light, with hollow bones. In several forms the head was larger than the entire body. Some pterosaurs had tails, while others were tail-less. Some fossils even show signs of hair covering the body. Many pterosaurs lived a similar life to the modern seagull and the albatross.

Picture credit: google