After spending 17 years alone underground, billions of red-eyed cicadas are emerging for their final act: to meet a partner, breed and die.
The phenomenon is breaking wooded areas on the U.S. East Coast into a deafening buzz.
(SOUNDBITE) (English) MICHAEL RAUPP, EMERITUS PROFESSOR OF ENTOMOLOGY AT THE UNIVERSITY OF MARYLAND, SAYING:
"This is just a spectacular event. I mean, there's nothing else like this on the entire planet Earth, even in the entire universe.’’
Tourists and scientists have been eager to study this rare event.
The biggest questions are: Is climate change affecting cicadas' life cycles? And if so, then how?
First, a bit of background.
After cicadas mate and the eggs hatch, the larvae fall to the ground and burrow into the Earth.
They dig out solitary chambers and begin growing as they feed on tree sap
until it is time to re-emerge and repeat the cycle – 13-17 years later.
''… I think they're some of the most beautiful creatures on the planet…"
Dr. Michael Raupp, is a cicada enthusiast and Professor Emeritus of Entomology at the University of Maryland.
"One misconception is they've been hibernating underground for 17 or 13 years. That's not the case. They simply have been developing very slowly underground for the last 17 years, growing from the size of a grain of rice to about this big and it's going to take 17 years to do this."
The cicadas emerging this year make up Brood X (pronounced "Brood Ten").
They're the offspring of insects that emerged in 2004 – the same year that Facebook was launched.
Some insects pop up four years too early or late.
But scientists noticed that a large number of the latest Brood X batch showed ahead of schedule - back in 2017.
Entomologists suspect that could be related to air temperatures and surface soils increasing due to global warming.
Evolutionary biologist at the University of Connecticut, Chris Simon, explained that a warmer climate makes for a longer growing season for the trees they feed off.
In some areas in recent decades, cicadas are getting bigger and surviving longer.
Simon says, eventually, we could see 17-year cicadas QUOTE "escape through time" and permanently change to a 13-year cycle.
Going forward, the question is whether the species will be able to adapt rapidly enough to keep up with climate change.
The Brood X batch will only live for about three weeks, before the lengthy cycle starts all over again.