Wednesday, September 19, 2007
Walking Sticks
One of the many advantages of being married to Liz, is that I get to see a fair number of walking sticks, for she has extremely sharp eyes for picking out odd little critters. Walking sticks belong to the insect order Phasmatodea (from the Greek phasma, meaning phantom, due to the unique ability of these insects to "disappear"). There are almost 3,000 species worldwide, with most being tropical or subtropical; the largest is over a foot long and is the longest insect.
Our specimen is Diapheromera femorata, the northern walking stick. I have been under the impression that they are much less common than when I was a boy, but was never completely sure whether that was true or whether I just don't pick them out as well now. However, I'm now convinced they have become scarcer, for I read that a hundred years ago in the midwest, they were so common that they were an important pest; the adults live primarily in the canopies of trees, eating the leaves, and the insects would become so thick that trees were denuded. The walking sticks lay their eggs just by dropping them to the forest floor, and apparently back then they were so numerous it would sound like it was raining. Alas, insecticides and mankind's general careless destructiveness has made the finding of a walking stick an occasion to grab the camera.