Some workers believe that Odonata adopted an aquatic larval stage during the Lower Permian, perhaps because their prey lived in aquatic habitats. In any event, several groups of Odonata existed by the Late Paleozoic, though only three members of this group survive today. On the right, an emerging adult dragonfly. The transformation to the adult form sheds the gills in favor of two pairs of wings. The newly emerged adult expands its wings by pumping blood into them.
Dragonflies are generalists, that is, they eat whatever suitable prey is abundant.
Oftentimes, they hunt in groups where large numbers of termites or ants are flying, or near swarms of mayflies , caddisflies, or gnats. Maturing dragonfly larvae feed very intensively, as do females when developing their eggs. Studies show that food shortage may limit reproductive behavior. Dragonflies do not hunt in cold weather. Damselflies, however, are not as limited by temperature and have been observed hunting during cold spells.