Friday, June 13, 2008

Green dragonfly

A green dragonfly, like some sort of living emerald creature, hovered over the stream. I'm sure it's quite common. After all, I've seen blue and red damselflies, and there are brilliant green ones as well. But I'd never seen this particular blue-green , so I had to get a photo of it.
Afterwards, I thought to myself - I could have capture it and kept it in a jar for all to see. (Zookeeper mentality) Or, killed it, and put it on a paper with a pin and a a carefully written Latin name. (Museum mentality) But really, all I wanted to do was capture it on film. But that's not enough. It shows the insect, but doesn't describe what he did.
He flew in all directions. He hovered, then shot backward, went straight up, swooped, looped, and made a perfect three point landing on a leaf. He held still long enough for the picture, then lifted off again, hovered in one place, then shot into the shadows - a glint of green in the dark, like a twinkling Christmas tree light.
I had to find out how he did it. I read that dragonflies are the masters of flight. Their wings are the exact opposite of our airplane wings - instead of using the airstream and taming it, they create disturbances and eddies that twirl them around. They are masters of unstable aerodynamics. They deliberately create and use turbulence with their 4 wings - each wing independent of the other and one third to one half of their body mass devoted to flight muscles. They are the fastest insects on wings, (clocked at 35 mph!) and can lift more than double their own weight (human aircraft can't even begin to approach that!).
Here is the book I read:
Spineless Wonders by Richard Conniff. (Strange tales from the invertabrate world.)


Bernita said...

They are very beautiful. Saw one once with scarlet filagree wings.

Travis Erwin said...

Interesting. I see these guys all the time but never knew much about them.