Wings are extensions of the cuticle and not modified appendages. Wings may have first evolved to help absorb heat, then developed further for flight. Other views suggest wings may have initially served for gliding, as gills in aquatic forms, or even as structures for swimming. Dragonflies were among the first to fly and have two coordinated pairs of wings. Modifications are found in groups which evolved later.
Butterflies have overlapping anterior and posterior wings.
Head segments are fused while segmentation is apparent on the thorax and abdomen. The thorax has three pairs of walking legs and the wings.