They’ve been lurking underground for a long time. Down in the darkness they tunnel, burrowing far beneath lawns and sidewalks and forests, shoving slowly between grains of soil, feeding on tiny sips of sap from tree roots. They’ve been down there quite a while: seventeen years is a long time to wait for anything.
This is the year that the periodical cicadas of Brood X have their brief moment in the sun.
There are many species of cicada, and around here in upstate New York we enjoy the late summer song of the annual cicada—that melodic cry that’s a mix of buzz saw and car alarm, blaring from the treetops in the hottest days of August. Annual cicadas are a different species from the seventeen-year ones—they spend only a few years below ground before emerging in late summer to serenade us.
Although they are unnervingly big and loud, these creatures are absolutely harmless—they don’t bite, they don’t sting. They don’t eat crops, harm gardens, pets, or children, or do any significant damage to trees.
Sadly, we’re not within the range of the spectacular Brood X, which covers a large area slightly to the south of us. It’s just one of several broods of those mysterious creatures, the periodical cicadas, that emerge every seventeen years. (There are also some species of thirteen-year cicadas.)
Why wait seventeen years, and then emerge all together in such vast numbers? They’re wielding a strategy known as predator satiation. If you’re small, clumsy, slow-moving, and deliciously crunchable, you’re very likely to be eaten by the thousands of predators lying in wait for the feast. But even tens of thousands of predators can’t begin to eat all of the billions of periodical cicadas, all emerging at the same time.
Never was a genus of insects so well-named: Magicicada. It does seem magical, all those miniature monsters silently rising from the ground, like when Jason sowed the dragon’s teeth and the skeleton warriors appeared.
The cicadas who don’t immediately become part of the food chain wend their way to a nearby bush or tree trunk. Then the brown, ungainly nymphs miraculously shed their skins to become a sparkling fresh creature, with wings of transparent silver and mad ruby eyes.
Then they make their way up to the treetops, and begin to sing—or rather to vibrate a membrane in their abdomen, which produces that echoing sound. The males belt out their demented chorus to attract the ladies, and for a few brief weeks, it’s an orgy of song and sex. And then it’s the end. Then they all die, all the mad singers. But the eggs they leave behind soon hatch, and then another brood goes underground.
Until seventeen years from now, when they’ll rise again, like a spring tide rising under the moon.