This weekend, I was trying to evade the mosquitoes swarming around me when I saw a much larger insect flying slowly down the trail. It soon landed on a vine a short distance away and I recognized it as a click beetle.
Although this click beetle did not have the glowing spots that had first made me fascinated with click beetles, its prominent eye-spots, large size, and loud clicks still made it very impressive.
The big spots on top of the beetle are not its real eyes.
For a demonstration of the clicking behavior, watch the video below. If you happen to find a click beetle yourself, I do not recommend that you attempt to provoke it into clicking. As I discovered somewhat painfully, when clicking fails to deter the harasser, the beetle may resort to biting.
If you watch the slow-motion part of the video carefully, you can see that the 'jump' is not caused by the beetle snapping back against my hand (as I had initially thought). Instead, the beetle lifts its head away from my hand and then the rest of its body just pops into the air. The key to the click and jump is the spine that extends down from the underside of the head.
The underside of the Texas click beetle. Note the spine used in clicking and the sharp mandibles used in biting.
The beetle produces the click by first catching the end of the spine into a notch, which prevents the beetle from moving as it contracts a large muscle that connects its body segments. Then, when the spine slides out of the notch, the energy in the muscle is rapidly released, propelling the beetle into the air.
No comments:
Post a Comment