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Smithsonian National Museum of Natural History
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See caption. On warm evenings, the cicada nymphs emerge from the ground and crawl a short distance to the closest tree or vertical surface over a period of a few hours. The nymph's "skin," or exoskeleton, splits along the top of the head and back of the thorax, and the adult begins to emerge.

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Under the cover of darkness, the adult maneuvers out of the nymphal "skin." The white color means the cicada is still soft and prone to drying out. At this stage, the adult can only move slowly, making it very vulnerable to predators.
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Over several hours, the adult cicada pumps "blood" or hemolymph from its abdomen into its wing veins --- expanding the folded wings .

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Most adults hang from the nymphal "skin" or exoskeleton while they pump fluids from their abdomen and their exoskeleton hardens and then turns black.

 

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Male cicadas call from trees. Each individual male tries to call louder than the next in order to convince females to chose them for mating.

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The sound is made with structures known as tymbals which are located on the sides of the first abdominal segment, near the top just behind where the hindwings attach. Large muscles contract, causing the tymbal surface to bend inwards which produces a vibrating click. These vibrating clicking noises are enhanced by a large air chamber that extends well into the abdomen. Repeated contractions by thousands of cicadas can create a spectacular din. Females chose the male that interests them with a flick of their wings which stimulates the male to come closer.

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After mating, the female deposits her eggs in the treetops. Look for her ovipositor stuck into the twig. To her right there are two other wounds in the twig where she laid eggs.

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Two adult cicadas (male on left) mate on a branch. Firmly anchored to the twig with their legs and mouthparts, the coupling lasts at least an hour. These adults may also be feeding.

 

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Cicadas do not bite or sting.

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A female lays up to 600 eggs in several different slits she makes in treetop twigs. Four to six weeks later, the tiny hatchlings float down to the ground. Branch tips at the tops of the trees die off from the female's egg laying activities. Only two percent of the hatchlings survive.

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The nymphal "shells" collect at the base of the tree after the adult cicadas have molted out and flown up to the tree tops.


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The tips of trees turn brown after the cicada females lay their eggs in the new growth. It does not damage most trees, in fact it has a natural pruning effect on most large trees.


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