Scientists believe that the wings could have developed from the gill-like projections possessed by the insects which lived in water according to episcopal theory (Engel, 2005). The theory states that the gills evolved over a long period after which they extended into the trachea of an adult insect in the form of flaps. These wing-like flaps enabled the primitive insect to jump over short distances but soon evolved further into the modern wings for flying, gliding, and diving.
On the other hand, the paranodal theory states that the wings just emerged from protrusions at the back of an insects’ body living on land (Hall, 1998). It is quite remote to imagine that wings evolved from insects living in water since the modern insects live in terrestrial habitats. Insects are thought to be the first creatures to live on land. Winged insects emerged about three hundred million years ago according to the fossil record; however, no clue exists about the fossil background of the original insect ancestors.
Research into the fossil history of the dragonfly for instance; reveals a close relationship in terms of physical features between the dragonfly fossils of the Carboniferous period and the existing ones. This fossil period that is characterized by the emergence of the dragonfly matches the time when other insects evolved but without wings. Insects, therefore, existed before they developed wings but then underwent extensive modifications during their evolution to acquire their modern wings (Hutchins, 2006). Insects evolved wings to fly.