Get Ready: The Cicadas Are Coming

After spending 17 years underground, a cicada brood known as the Magicicada Brood II is getting ready to emerge on the East Coast this spring.

The last bit of the name comes from their heritage: they are the offspring of the cicadas that ventured above ground in 1996. And if they follow in the foots of their parents, they will appear in Connecticut, Maryland, North Carolina, New Jersey, New York, Pennsylvania, Virginia and Washington D.C.

Exactly when the expected party plans on arriving is hard to tell in advance: historically they've appeared when the stop 8 inches of soil reaches a warm 64 degrees.

Their emergence actually marks the end of their lives, as the cicada only comes above ground to breed and die almost instantly.

The effect, however, can be cumbersome for people that inhabit the regions where the insects live as some areas can see as many as a million cicadas per acre.

"It can be like raking leaves in the fall, except instead of leaves, it's cicada bodies," cicada researcher Dan Mozgai told National Geographic.

What's more, the distinctive cicada love song used in mating can be loud - really loud.

Scientists have yet to discover why cicadas appear in 13- and 17-year cycles, though one popular theory is that the timing is a defensive mechanism as their infrequency makes it harder for predators to anticipate their arrival. A study by the University of Campinas in Brazil demonstrated, for example, that a cicada with a 17-year cycle and a parasite with a two-year cycle would only overlap twice every 100 years.

Those types of cicadas that do not breed on a multiyear cycle, like the tibicen cicadas, are regularly hunted by the cicada killer wasp who lays eggs on its prey, leaving the larvae to slowly kill the cicada and feed off its carcass.