SCIENCE

Dragonflies Are an Odd Combination of Beautiful Things

Don’t be misled by their dainty appearance. These ornaments of summer are aggressive predators, amazing fliers and bizarre suitors

Richard Conniff

July 1996

This image shows an about 1.6 inch (4 cm) large male Yellow-winged Darter (Sympetrum flaveolum) from the side Wikimedia Commons

The dragonfly has been evolving for roughly 300 million years. Fossils show that in its glory days it had the wingspan of a crow. Even in its present size, though, it has the ability to make humans who try to collect it with nets look inept. Dragonflies are among the fastest and most acrobatic insects on wings. Wind tunnel tests show they are masters of what aviation engineers call unstable aerodynamics. Whereas humans strive to minimize turbulence over aircraft wings, dragonflies' wings deliberately generate and exploit turbulence.

These syringe-shaped members of the order Odonata are unconventional when it comes to mating and reproduction, too. In their underwater larval stage, before they metamorphose into the familiar fliers we recognize, they are superb swimmers and deadly predators. All of which helps explain why scientists, conservationists and other admirers like to catch these beautiful creatures (if they can) and study them up close.