The life cycle of Brood X, from emergence to death.

Waiting in a tunnel
Weeks ago, an inch-long cicada nymph finished excavating the tunnel it will take to the surface. Since 2004, it has been growing and molting, drinking a fluid called xylem from plant and tree roots through a straw-like beak.

Dramatic entrance
When the soil about a foot below ground warms to 64 degrees, probably on an evening that is humid but calm, it will crawl out. Half the brood will emerge within a couple of weeks.

Empty slide for space

One last shed
Once out, the nymph will climb something vertical — the nearest tree, flower, wall or pipe will do — and molt for the last time.

Adulthood at last!
After wriggling out of its brown shell, it is now over an inch long and almost completely white, with the bright red eyes that identify it as a periodical cicada. It is extremely soft and vulnerable, a tasty snack for birds, dogs and other creatures.

Adjusting to a new body
In a few hours, its body will turn bluish black and orange, like other members of Magicicada septendecim, the largest of three Brood X species. In several days, it will be able to fly — and call.

Discovery: It’s male Empty slide for space
We know this one is male because its abdomen ends in a rounded dome; a female’s would end in a point.

Once cicadas can fly, the lives of males and females are quite different.

Time to join a chorus
Only males can call, using vibrating membranes called tymbals on either side of their hollow abdomens.

They call for different reasons; if you pick one up, you may hear an alarm squawk. But the main reason for calling is to attract females. Around dusk each evening, our cicada will add its call to a chorus of other males hoping to find mates. Each species’ chorus has a distinctive sound.

When a female is interested, she will respond with a wing flick, which sounds like a snap. The male will notice and fly toward her, changing his call to a more complex one.

Changing his tune
With each call and flick, he will approach closer. The female listens for acoustic cues to make sure he is the right species. Competition can be fierce, and a rival male may try to drown out his song.

Empty slide for space

Mating rituals
Once he is very close to the female, he will stop calling and begin to touch her with his forelegs. If she is receptive, they will mate, tail to tail. A male can mate many times, but a female usually mates only once.

Egg-laying
Within an hour after mating, the female will find a tender tree branch and slice it open with her swordlike ovipositor. She will insert up to 30 eggs, then make more slits until she has deposited a total of 400 to 600 eggs.

Empty slide for space

Empty slide for space

Then, it’s over
The cicada and its mate will die after two to four weeks above ground. Their nitrogen-rich bodies make excellent (but stinky) fertilizer.

Hatchlings head below
Six to 10 weeks later, tiny nymphs will hatch and drop to the ground. They will burrow below with their mole-like forelegs, latch onto a root and begin to feed and grow.