Dragonflies are among the oldest flying insects on the planet. As insects evolved to fill the land they began to exploit every niche available. The soil, the plants and even the air. Following those early insects were organisms all too ready to hunt them. Dragonflies were one of the first to exploit the air as a hunting ground, millions of years before birds and bats. The fact that dragonflies have not significantly changing over millions of years is a testament to their efficiency and precision as aerial predators.
This is a Skimmer Dragonfly (Family Libellulidae) that I found cruising the flower garden by Springbrook Nature Center. It landed on a large chunk of granite and I couldn’t think but think about the fossil dragonflies with three-foot wing spans. This Skimmer landed on a rock that could very well be younger than some of this dragonfly’s own ancestors.
Dragonflies start life in the water as aquatic nymphs. There they hunt other small invertebrates and even the occasional vertebrate. Once the emerge from the water and emerge in their adult stage they must wait for their wings to harden. Dragonflies initially have their wing folded together. As they harden the strong muscles of the thorax force the wings to the sides, where they remain for the rest of the dragonfly’s life. Like fighter jets with rigid wings for increased aerial maneuverability the dragonflies cannot fold their wings. The are truly masters of the skies.
I have always wondered why they are called dragonflies. They don’t really look like dragons of European or Eastern legends. They do eat insects on the wing but otherwise they don’t seem to share much in common with the mythical dragons we are familiar with.
I found this Common Darner (Anax junius) on a run near my house. It had been struck by a passing car and was nearly dead when I found it. The last third of its abdomen was missing and it was missing portions of several legs. It wasn’t going to make it. In its throws of death this large dragonfly showed me how I think dragon flies got their name.
Most of us see dragon flies from above, we usually don’t look under the belly of the beast. As this dragon fly was dying it nearly continuously opened and closed its mouth, revealing the deadly tools of its trade. Behind the seemingly innocent ‘face’ are the deadly tools of an efficient predator.
The large appendages hidden from sight are designed to dismember and consume their prey. Dragonflies eat other insects, and all insects are covered with a hard chitinous exoskeleton. The dragonfly bypasses this defense with powerful jaws that simply puncture, pry and pull the insect apart.
The view from below is much more menacing that the traditional dorsal view that is commonly used.
If you look at the dragonfly’s head through an evolutionary lens you begin to see an organism that is superbly adapted to its environment. Fighter jets have bubble-like cockpits to allow the pilot full view around them during extreme aerial maneuvering. The dragonfly doesn’t have a cockpit, it has one better, its eyes are raised above an around the head allowing for an extremely large field of vision. Each eye is actually composed of thousands of smaller lenses (compound eye). Each lens perceives a different view, the dragonfly can track motion and light changes across each lens to detect the slightest motion.
In the picture above you can actually see the individual lenses of the eye. The reflected light also reveals the shape of each lens, a nearly perfect hexagon.
Imagine you are a small insect flying through a garden. You are going from plant to plant looking for your desired food source. You also have compound eyes and you are constantly looking for threats from above or below. You pass through a shadow when from behind you all you see is the following image…
This Dragonfly died moments after I took these pictures. It taught me more about dragonflies than all the others I have seen in my life. I now see these amazing predators in a new light. They are masters of their world and they truly are dragons of legend.
Up Next: Garden Assassins