Billions of cicadas are expected to make an appearance on the East Coast and in the Midwest this April as two broods of the insect emerge. Making an emergence this year are Brood XIX, or the Great Southern Brood, which emerges every 13 years, and Brood XIII, or the Northern Illinois Brood, which emerges every 17 years. "It's rare that we see this size of double-brood emergence," Jonathan Larson, an entomologist and assistant professor at the University of Kentucky, told CNN.
While double-brood convergences aren't rare, these two broods haven't emerged together in more than 200 years, and they will not again for another 221 years.
While the emergence will be the "most macabre Mardi Gras that you've ever seen," said Larson, the cicadas themselves are essentially harmless. They emerge to breed and die promptly after. The broods also consist of multiple species of cicadas. "The outcome of this will produce hybrids, and only the cicadas and Mother Nature know what the outcome will be," Mike Raupp, a professor emeritus at the University of Maryland's entomology department, told BBC.
Geographically, the broods of cicadas may only see minor overlap. Areas in central Illinois are most likely to see both broods emerge around the same time. "If you're lucky enough to live in an area where these things are going on, get your kids out there," Gene Kritsky, a professor emeritus of biology at Mount St. Joseph University, said to NPR |