Which creature existed before the dinosaurs, is an aerial genius, and can detect things we can only witness through slow-motion cameras?
Predecessors to the Dinosaurs
Dragonflies were some of the first winged insects to evolve, about 300 million years ago. When they first evolved, their wingspans measured up to two feet! In contrast, today’s dragonflies have wingspans of about two to five inches.
Although in this feature we speak of dragonflies in a general sense, there are more than 5,000 known species of them, each with its own characteristics.
The Dramatic Entrance
Dragonflies begin as larvae. During this almost 2-year stage, they live in wetlands such as lakes or ponds across every continent except Antarctica. Despite their small size, their appetite is huge, and they are not picky eaters. In their larval to nymph stages, they will eat anything they can grasp including tadpoles, other insect larvae, small fish, mosquitos, and even other dragonfly larvae.
After their nymph stage, dragonflies emerge as if they were reviving from the dead. They crawl out of the water, split open their body along their abdomen, and reveal their four wings- along with their new identity. Then, they spend hours to days drying themselves before they can take to the skies as the insects we know and love.
Once a dragonfly is dry and ready to fly, their voracious appetite continues. As usual, they’ll eat almost anything, but now they will only eat what they catch mid-flight. These feasts consist of butterflies, moths, bees, mosquitoes, midges, and, yet again, even other dragonflies. They seem to embrace the motto “every fly for themself.”
Engineered for Optimal Flight
Dragonflies emerge after their larval stage as masters of the air. Their four independently moving wings and their long, thin bodies help them maneuver the skies. They hunt and mate in mid-air and they can fly up to 60 miles per hour. They are also able to fly backwards, sideways, and every which way in a matter of seconds or less.
This incredible ability requires excellent vision. (Or else we would likely see them crash much more often!) Thankfully, dragonflies have just the answer. Their head mostly consists of their eyes. Their multiple lenses allow them to see nearly everything around them, covering every angle except one: right behind them. The insect’s vision not only reaches far and wide, but allows them to see the world at faster speeds than we can.
How are human activities impacting dragonflies?
Since dragonflies consume a variety of organisms, and rely on healthy bodies of water to grow, they are considered important environmental indicators. In other words, when dragonfly populations plummet, conservationists have something to worry about. Nymphs and dragonflies will eat just about anything, so they will only go hungry if there is no available food. Looks like those big appetites came in handy after all.
Declines in dragonfly populations also indicate water pollution and habitat loss. These are consequences of agricultural methods that favor chemicals and synthetic fertilizers, and forest management that disregards the importance of maintaining balance within an ecosystem. One solution is regenerative agriculture which ensures fewer toxins in our environment.
Overall, the more green (and blue) space for wildlife, the more likely these iconic insects will thrive.