Sunday, July 11, 2010

Damsels and dragons

click photos to enlarge
I'm naturally curious about the things that I photograph. Consequently I often find myself learning something about areas in which I am fairly ignorant, and into which, without the prompt of photography, I would hardly ever venture. Today's images are a case in point. I have no more interest in insects than the average layman, but these two were presenting themselves very conveniently and so I took a couple of shots. Here's something of what I learned when I decided to find out precisely what they were. The information comes from the very helpful British Dragonfly Society website.

Damselflies and dragonflies belong to the insect order Odonta. This name means "tooth jawed" after their serrated mouthparts. Odonta is subdivided into two sub-orders, Zygoptera (damselflies) and Anisoptera (dragonflies), and a number of distinctive features separate the former from the latter. Damselflies are most easily distinguished by their habit of holding their wings along their abdomen when at rest: dragonflies hold them out, often at right angles to their body. The more sharp-eyed observer can also note that the wings of the damselfly are almost equal in size and shape whereas the dragonfly has forewings that are obviously larger. Finally, the eyes of the damselfly are always separated: those of the dragonfly always touch even if only at a single point. Armed with that information it was clear that my two subjects were damselflies. In fact I knew that of the larger winged insect before my research began, though that was probably the sum of my knowledge of that sub-order.

The other information I sought was in connection with the name. Why dragonfly?  It seems that they used to be called "horse stingers" from the, probably mistaken, belief that they bit horses making them start. In fact it was probably the flies that were the dragonflies' prey that caused alarm in the horses, and the nearby presence of the larger insects led them to be blamed. Damselflies were sometimes called "Devil's Darning Needles" from the belief that if you fell asleep by a stream on a warm summer's day they would use their slender bodies to sew your eyelids closed! As to the origin of the "dragon" part of the name, I anticipated some piece of folklore involving a fair damsel and a wicked dragon, but alas, I could find nothing.

I have neither the lens nor the inclination to pursue insects as a regular photographic subject, so for these shots I used the Zuiko 40-150mm at its maximum extension and then cropped the images slightly.

photograph and text (c) T. Boughen

Photo 1 (Photo 2)
Camera: Olympus E510
Mode: Aperture Priority
Focal Length: 150mmmm (300mm/35mm equiv.)
F No: f5.6 Shutter Speed: 1/500 (1/160)
ISO: 200 (100)
Exposure Compensation: -0.7 EV
Image Stabilisation: On