Something strange is going to happen next month.

It's not once in a lifetime, exactly, but for every kid listening, it'll be once in your lifetime so far.

On the east side of the United States, billions of insects of a brood not seen in nearly two decades are going to crawl out of the ground simultaneously,

sprout wings, and darken the sky.

This brood is known as Brood X.

It is a veritable army of insects belonging to three species of cicada.

It invades our country once every 17 years.

Last time they emerged, witnesses said it was like the ground itself was moving.

Their collective singing was enough to make people cover their ears when they left the house.

And entomologists didn't sleep for like two months. Soon, there will be more cicadas flying around a handful of U.S. states than there are people on the North American continent.

The largest of them will belong to a species known as the Faro Cicada.

Maga Cicada Septendacium.

They've been waiting. I'm Mackin. This is species.

Welcome to the show. Today's episode is one of the most requested episodes of all time, and I think

this is just a case where everybody knows what these animals do,

but almost nobody knows why or how they do it. And so I'm going to explain all the relevant

science today. In other news, I finally was approved to announce last Friday that I've teamed

up with McMillan's new imprint, Neon Squid, to release my first children's book,

Animal Sidekicks. It's about my 59 favorite symbiotic relationships. I sent out an email

with way more details to my mailing list, but you can find most of the same information by clicking

on the link in the show description to my new book. It'll be on sale February of next year.

I know that's a bit of a wait, but that's just publishing.

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