 |
| A blue dasher, Pachydiplax longipennis, perched on a twig, contemplating its own awesomeness. |
With a title like "Dragons, Flies, and Dragonflies," it's only natural that my first post should be about dragonflies. They are, by far, my favorite insects. Why?
1. They have the coolest names of any insects.
Insects have some pretty cool-sounding names: assassin bug, antlion, beewolf, even death's-head hawkmoth. But, seriously. DRAGONfly. I might be biased because of my love of fantasy, but I am of the opinion that nothing is cooler than dragons. And if you think there's something cooler, dragons can probably eat it.
But the coolness doesn't end with "dragonfly." A dragonfly is just any member of the order Odonata, suborder Epiprocta, infraorder Anisoptera, which contains about 3,000 species. Odonata means "toothed ones," which is pretty cool as far as order names go. But when you get down to the genus level, you see names like meadowhawk, boghaunter, and my personal favorite, shadowdragon. Keep in mind that those are just genus names. Go one step further down the taxonomic ladder to species, and you're spouting names like ebony boghaunter, black meadowhawk, smoky shadowdragon, and... dragonhunter.
WOAH BOY, we just found the only thing cooler than a dragon, a dragonhunter. But what would be foolish enough to hunt a dragon? Only a bigger dragon, of course! Which is exactly why the dragonhunter is so-named; this 3.5-inch (9 cm) monster will take down any insect its own size or smaller, and that includes every dragonfly in its range. Which brings me to my next point about dragonflies...
2. They are the BEST predators.
 |
| A female eastern pondhawk, Erythemis simplicicollis, dines on an amber-winged spreadwing, Lestes eurinus. |
What animals pop into your head when I say "predator"? Probably something like a shark, or a lion, right? Well, what if I told you that great white sharks only succeed in catching about half of the prey they chase after? And for lions, it's even worse: three out of four of their hunts fail! But dragonflies?... They succeed in catching their target 95% of the time.
Unlike the shark and lion, which give chase to their prey in the hopes that they can catch it, dragonflies calculate the velocity of their target and intercept it. In the space of a second, their simple brains decide how far away their prey is, how fast it's moving, and in what direction. And 95% of the time, they are right.
In other words, dragonflies are better at math than me.
But that's not all. Dragonflies display selective attention when hunting. This means that their brains can lock onto one insect in a swarm and filter out all others, much like how a person can filter out background noise to hear their friend talking at a concert. Until this discovery, selective attention had only been demonstrated in primates.
So, dragonfly brains can single in on one target amid a swarm and calculate velocity for a perfect kill. Everything about them makes them more efficient killers, from their huge eyes (the largest of any insect), which give them a nearly 360° field of vision; to their spiny legs, which cage in prey so there is no escape; to their serrated jaws that mash prey into a wad of snuff to be devoured. Oh, and did I mention their wings?
3. They are the BEST fliers.
There are two types of insect flight: direct and indirect. Most insects fly using indirect flight, in which the wings are lowered and raised by expanding and contracting the entire thorax.
Only two orders of insects, Ephemeroptera (mayflies) and Odonata (dragonflies and damselflies), use direct flight. In direct flight, each wing has its own group of muscles and can move independently. In Ephemeroptera, the hind wings are reduced or absent, making mayflies less agile and graceful on the wing than odonates. Dragonflies and damselflies have four wings, and each can be raised, lowered, and rotated forward or backward independently of the others, making odonates masters of flight. They can move straight up or down, hover in place, make hairpin turns instantly, fly backwards, and even fly upside down when they need to! No other animals are as aerially adept!
Because of their wider hind wings, dragonflies are faster, more powerful fliers than even their damselfly brethren. The southern giant darner, Austrophlebia costalis, is believed to be the fastest dragonfly, and has been clocked flying at 36 mph (58 km/h), which comes to 126 body lengths per second for the 5-inch (13 cm) insect. For a 6-foot (1.8 m) human to travel that fast, they would have to run at a speed of 515 mph (829 km/h)!
Dragonflies are truly amazing fliers, which makes sense considering how long they've been flying.
4. Their design is so perfect, they've remained nearly unchanged for 300 million years.
Fossils of gigantic dragonfly ancestors have been found in rocks dated as far back as the Upper Carboniferous, a geologic period that lasted roughly from 323 to 299 million years ago. Scientists have named this order of giants Meganisoptera, and it contained the largest known insect of all time: Meganeuropsis permiana. This hawk-sized insect had an estimated wingspan of 28 inches (71 cm), and a body length of nearly 17 inches (43 cm). The land was dominated by amphibians during this period, and it probably ate small amphibians as well as other insects.
Apart from their size, meganisopterans only differed from modern dragonflies in a few key ways: they had a relatively simpler pattern of wing veins, and their wings lacked nodi (wing notches) and pterostigmata. A pterostigma is a thickened cell on the anterior edge of a wing that makes gliding easier.
 |
| An eastern amberwing, Perithemis tenera, with wings showing pterostigmata and nodi, as all modern dragonfly wings do. |
Some scientists have taken to calling meganisopterans "griffinflies," because, you know, griffins are obviously bigger than dragons. -_- As for me, I think I'll stick to meganisopterans, or maybe "wyvernflies." Wyverns are the simpler relatives of dragons, just as meganisopterans were simpler relatives of modern odonates. While a dragon usually has four legs, a wyvern has only two.
Dragon – legs = wyvern, so dragonfly – wing veins = wyvernfly?
Hey! You know another cool thing about dragonflies?
5. They come in a dazzling array of colors and patterns.
Most people would probably say with confidence that butterflies are the most beautiful insects, and with good reason, but I would like to make a case for dragonflies. They show striking colors and patterns on not just their wings, but their bodies and eyes as well. I'll let a few of my photos do a little talking here, but they don't make a complete case for the dragonfly's beauty; I would recommend doing a quick Google Images search of "most beautiful dragonflies."
 |
| Look at the gorgeous, multi-colored eyes on this blue dasher. |
 |
| The widow skimmer, Libellula luctuosa, has a metallic blue body and black and white wings. |
 |
| Behold the brilliant, Halloweeny wings of the Halloween pennant, Celithemis eponina. |
Do you love dragonflies yet? If not, I've still got an ace up my sleeve.
6. They always look like they're smiling.
They do. I'm serious. Just look at the huge smile on this swamp darner (Epiaeschna heros).
 |
| Happiness is a smiling dragonfly. ^_^ |
This species illustrates the happy demeanor of dragonflies better than any other I've seen, due to the caret-like (^) lines on the eyes, and the yellow "smile" line across the face.
But it's not just this species that wears a perpetual smile. It's all of them. Every one. Just look for a smile line on any dragonfly face. It might not be highlighted like it is on the swamp darner, but it will be there.
It's the icing on the cake of the dragonfly's awesomeness.
