While fantasy is one of my writing fortes, and I love writing fantasy and I love dragons, this blog adventure is a fact-finding mission on the wee dragons in our real world. The little ones with multi veined wings that we love to see land on our plants. They are (seemingly) happy little insects who do us no harm. Of course, I’m talking about dragonflies. And don’t we all love dragonflies? Did you know it’s illegal to kill them without a permit (I expect that’s just a deterrent since who’s going to get a permit to kill dragonflies)? And did you know they’ve been around for almost forever? Well, 325-million-year-old fossils of very large dragonfly ancestors with wingspans up to about 750 mm (30 in) have been found. That’s older than dinosaurs.
Then there’s the dragonfly’s “cousin”. Have you ever heard of damselflies? Chances are, when you’re admiring a dragonfly, you might actually be admiring a damselfly. If you did know about damselflies, do you know the differences between dragonflies and damselflies? There are obvious differences in their eyes, bodies, wing shape, and their position at rest (what’s left after that, I’m wondering?). Dragonflies’ eyes touch, or almost touch, while damselflies eyes are separated and usually appear to be on each side of the head. Dragonfly bodies are usually stocky and their wings are dissimilar with hind wings that are broader at the base, whereas damselfly bodies are long and slender and their wings are all similar in shape. Most interestingly, when dragonflies are at rest, their wings are held open, either horizontally or downward, while damselflies wings are closed over the abdomen when they are resting. Did you have any revelations while reading the differences? I haven’t thought about damselflies in ages, so I certainly started seeing in my mind’s eye all the times I’ve seen what I thought was a dragonfly in the past decade or two, that in truth must have been a damselfly. (Don’t you love having knowledge at our fingertips?)
I think I could write a book on these insects and their abilities, their flying maneuvers, and their strategic methods, like how some dragonflies signal ownership with striking colors on the face, abdomen, legs, or wings, or how some species females have evolved behavioral responses, including feigning death to escape the attention of males because they strip their energy (are some of you gals out there laughing a little), but I’ll go for the basics.
Some fun facts:
Between them there are over 5,000 species of dragonflies and damselflies. Like much of the animal kingdom, dragonflies and damselflies both tend to be territorial as well as predatory (now you see what I wrote "seemingly" happy above). Dragonflies are some of the insect world's most efficient hunters as they manage to catch up to 95% of the prey they pursue. Luckily for us, both variety of these insects do not pose a threat to humans, although they might bite if they feel threatened, but the bite probably won’t break human skin. However, they do consume large quantities of mosquitoes, gnats, and other biting insects. No wonder we like them!
Dragonflies and damselflies have acute eyesight. In fact, dragonflies see faster than we do; our vision is in slow motion compared to theirs. They see about 200 images per second (makes me think of these new TV’s where you can watch a dozen shows at once), and they can see in all 360 degrees around them. Almost 80 percent of its brain is dedicated to its sight. Adult dragonflies have two large, multifaceted, compound eyes with nearly 24,000 optical units (ommatidia) each, which takes up most of its head. While damselflies have three simple eyes (ocelli) on top of the head, which are considered to measure light intensity.
With their ultra-thin membrane, hollow veined wings (yes, hollow veins! most of them anyway), dragonflies and damselflies are incredible, strong, agile flyers with highly controlled flight. In fact, I wouldn’t be surprised to learn that some of our new technology in flying was mirrored after dragonflies. They can fly further, higher and faster than most insects (70km/43.5 miles per hour) and in any direction, including backward, and can hover as well. When they’re in a high-speed territorial battle, Australian emperor (Hemianax papuensis) males can adjust their flight paths to appear stationary to the rival, lessening their visual approach. And the fuel they use to fly is body temperature – basking in the sun to bring their temperature up or hanging upside down or skimming bodies of water and touching the water briefly a few times to lower their body temperature.
Don’t let size fool you, we might assume that the dragonfly with its larger body might mean it would also be the largest overall insect. However, the insect with the longest wingspan in this family is the Megaloprepus helicopter damselfly or Forest Giant found in Central and South America. Their wingspan can grow as long as 19 cm (7.5 in) and their body length can be grow up to 13 cm (5.1 in). Some fossil Odonata ancestors have wingspans of more than 28 inches.
Sadly, the loss of wetland habitats threatens dragonfly populations around the world. We really need to be concerned about our planet; it’s our home. Maybe all you can do is reuse, or recycle, or donate, or dispose of toxic material properly. Do what you can to help our planet survive and thrive. When it dies, so will we.
In the meantime, enjoy the next dragonfly you see…or is it a damselfly?
Very interesting. How the heck do they know these facts??