Adult annual cicadas, including the pictured Dog-day Cicadas, have emerged from their subterranean dwellings. High up in trees most males are vibrating their abdominal tymbals (drum-like organs) in order to woo female cicadas with their “song.” Thanks to an abdomen that is relatively hollow, the sound is intensified, and very audible to human ears as a high-pitched whining drone, somewhat resembling a buzz saw. We associate it with the hot, humid “dog days” of July and August.
Annual cicadas emerge from the ground (where they have been feeding off of the sap of trees through the trees’ roots for two to four years) every year as nymphs. They climb a tree, split and emerge from their exoskeleton, or outer skin, and pump their wings full of fluid. After their exoskeleton dries, the adult cicadas (also called imagoes) head for the canopy, and males commence “singing” to attract a mate. Within two weeks mating takes place, eggs are laid in slits of live branches and the adults die. After hatching, the nymphs will drop to the ground and burrow into it with their shovel-like front legs. (Thanks to Wallie Hammer for taking and providing today’s photograph. Mating usually takes place in the canopy, and therefore rarely seen.)
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