Filed under: Insects
I was outside last night, staring intensely at M29 through the telescope eyepiece, when I became aware of a familiar rythm eminating from the woods…Katydids! This is the first time I’ve heard them this year. At their peak, they can become almost deafening in the night, the entire forest pulsing with their calls. I love it. Their name comes from their call, which some folks think sounds like, “Katy did, Katy didn’t.” Those who have grown up in the west or in a big city, may have never experienced this incredible sound event. The entire forest seems to pulse. When you have thousands of these really loud critters calling together, to me it sounds like a raspy “Shhh-Shhh.”
Katydids are members of the Tettigoniidae, or “Long-Horned Grasshoppers,” although they are more closely related to crickets. You can tell them apart from grasshoppers by the length of the antennae, which in Katydids are longer than the body.
Despite making such a prominent sound on summer nights, they remain inconspicuous visually. There are some good reasons for this: they live high in the forest canopy, rarely come down to earth except to lay eggs, and they look just like leaves!
I love cryptic animals, and the katydids are real pros at being inconspicuous. Our own common katydid, abundant in Eastern forests, is a pretty good leaf mimic. It is green, and its wing covers even sport veins and other leafy features. However, it is completely outdone by the tropical katydids, which have had more time to evolve cryptic features. Not only do some have perfect “leaves” as wing covers, complete with veins, the leaves also have insect holes, fungus spots, and lichens.
Not all katydids are cryptic, some going the route of intimidation rather than concealment. Looking like psychedelic bikers with multi-colored spikes and armor, these tough guys are willing to literally fight for survival. Watch out, they bite!
It’s no surprise that katydids go to such lengths to avoid becoming dinner. They are the main course in their habitat, the forest canopy. They are like the cows of the canopy, grazing on the abundant greenery, and becoming the food for canopy dwellers like monkeys, birds, and lizards. Everybody wants to eat katydids (they ARE pretty tasty!), so they have some pretty extreme selective pressure to develop camouflage or defensive weapons.