Cicadas are set to flood states this spring and in upcoming decades. What do we know about them?

Cicadas' life cycle is pretty unusual; they are gathered in the ground for the first 17 years, drinking sugar from the tree roots. Just after this long hibernation, they leave their beds, grow wings, and "sing." just to die within the next couple of weeks. However, there are "quicker" species of them, which spend "only" 13 years sleeping. This year, both of them are believed to fly.

How many, and where?

In an extraordinary natural event, scientists are projecting that the United States, particularly the East Coast, could see an astounding number of large flies – with estimates ranging from billions to possibly trillions. This phenomenon is expected to reach its peak in this region.

In a once-in-a-generation occurrence, the United States is witnessing the rare alignment of two cicada broods – the 13-year and the 17-year cycles. This simultaneous emergence, which happens only once every 221 years, draws significant attention. This year is particularly notable as Brood XIII and Brood XIX are set to appear in close quarters, with their habitats overlapping in Central Illinois, marking a remarkable chapter in the cicada's long history.

"Thomas Jefferson was president the last time these two broods came out, so is it rare? Yes," said Gene Kritsky, an entomologist at Mount St. Joseph University in Cincinnati, quoted by the NBC.

After this year, these two specific broods are set to collide again no sooner than in 221 years; that's a once-in-a-lifetime event.

Sources: Vox, NBC, NPR