In 2024, Illinoisans will see the largest number of cicadas emerging from the ground in over two centuries. A double brood emergence is coming.

Cicadapocalypse 2024

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Illinois and the rest of the US will be invaded by millions of cicadas this summer when two gigantic broods of the insect will be coordinating their uprising.

The size of the double brood emergence is predicted to be the biggest seen in 221 years.

Periodical Cicadas

Once every 13 or 17 years Periodical cicadas arrive in big numbers and this year two broods are coming.

Brood XIII makes an appearance every 17 years, while Brood XIX pops up every 13 years. This year, they’re going to have to learn to share, as they’ll be wriggling topside together.

According to a story at, it's those numbers, 13 and 17, that are behind why this summer can be referred to as, Cicadapocalypse 2024.

Thirteen years and 17 years are special because they’re both prime numbers, which means it’s really hard for a predator to have a cycle that syncs up with them,” explained mathematician Professor Hannah Fry in a TikTok video. “Also, they almost never synchronize with each other – 13 and 17, kind of missing each other – apart from every 221 years.


If millions of cicadas are turning the summer of 2024 into Cicadapocalypse, that means our trees and decks will be covered in billions of cicada eggs.

Illinois Cicadapocalypse 2024 Biggest Numbers In Over 200 Years

Once these insects crawl out from underground and shed their exoskeletons, the males will start making all that racket trying to attract a female so they can mate and help ensure the survival of the next generation.

Female cicadas lay their eggs, the eggs hatch, and the nymphs fall to the ground, starting the cycle anew.

One more thing you should know about cicadas as we prepare for an emergence not seen since 1803 and it's something that never crossed my mind about cicadas all the sex for survival.

CIcadas live with the threat of something similar to STDs in humans. And it leads to parts of the insect falling off.

As the sexually transmitted pathogen eats away at the cicada’s reproductive organs, the insect will pass it on to every other cicada they encounter. Eventually, the eating away becomes so severe the cicada’s butt actually falls off.



Maybe Dirty Cicada Orgy 2024 is a more realistic title than Cicadapocalypse.

LOOK: 20 of the biggest insects in the world

Stacker compiled a list of 20 of the biggest insects in the world using a variety of news, scientific, and other sources.

Gallery Credit: Andrea Vale

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