Weiss said those who are curious can head out with a flashlight once they notice these little holes in the ground and might be able to spot the insects weeks before they come out.

“If you catch them at the right time,” she said, “you’ll see a little cicada with red eyes, kind of peeking up from the side of the tunnel.”

Because they survive off nutrients from tree roots, cicadas don’t emerge in lawns, agricultural land or anywhere where trees might have died or been cut down. Once the soil rises to a certain temperature after the spring, periodical cicadas use it as a cue.

“They come out at night. So it’s very much a nocturnal event, which really makes it even all the more exciting,” Lill said. “(They) crawl out and then climb up a tree or a bicycle or your pant leg — whatever vertical surface. They’re not picky.”

They then begin a laborious process. The cicada’s shrimplike shell cracks open, and a ghostly white creature with red eyes leans back into a “diving board pose,” Weiss said.

“This is the most dramatic part,” she said. “John (Lill) and I were both here 17 years ago with little kids, and having the kids watch this transformation was magical for them and magical for us.”

After a few minutes, the cicada does “a mighty situp” and spreads its wings. A few days later it’ll look like an entirely different creature, dark-colored and hardened instead of white and soft.

That’s when the main attraction begins. Male cicadas perch on tree branches to sing — well, the sound is rather more like the vibration of a drum. Each species has a distinctive call, and the racket the males make attracts female cicadas from their own species.

So even if periodical cicadas from different broods emerge at the same time in approximate locations, they have evolved in such a way that their song pitches are distinct — not to the human ear but certainly to other cicadas — to prevent interbreeding and hybridization.

After a short dance and successful mating, the female cicada will lay her eggs inside the tree branches. This whole process takes about three to four weeks.

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