Tens of billions of noisy cicadas are set to pop out of the ground in the coming weeks in a rare synchronized event that last occurred 221 years ago. The winged insects are expected to appear across the Midwest and Southeast starting early May, in a double emergence of two different broods of periodical cicadas. These bugs spend a fixed number of years underground before coming to the surface to take part in a raucous mating ritual.
Thousands of cicada species can be found around the world, but periodical cicadas are distinct because they spend most of their lives underground, feeding on tree roots. After either 13 or 17 years, depending on the brood, the insects tunnel to the surface to begin a frenzied, monthlong search for a mate. Louderman said he hasn’t seen any reports yet of early cicada sightings. The insects usually pop up from underground once soil temperatures reach around 64 degrees Fahrenheit.