Billions of cicadas lay beneath the ground of eastern North America, feeding and fattening, waiting for the signal to rise and restart one of the most extraordinary life cycles in the animal kingdom. They are Brood X, an insect swarm of mind-boggling proportions.
What Are Brood X Cicadas?
Brood X cicadas crawl on a plant during their emergence in 2004. (Credit: Greg Hume/Wikimedia Commons)
The bugs belong to a group called “periodical cicadas,” named as such because they emerge only once every 13 or 17 years, depending on the brood. A brood, by the way, is simply a class of cicadas that happen to pop out of the ground at the same time — there are 15 in the U.S. They often consist of multiple species, all coincidentally synchronized. Brood X, or the Great Eastern Brood, spans more than a dozen states, and may be the largest among the 17-year cicadas.
