Well, they're already here really, bringing with them a host of disgusting and annoying sensations. Their immensely displeasing appearance. The sickening crunch that now accompanies your every step. The obnoxious buzzing (which studies have shown can reach 100dB, louder than a motorcycle engine).
If you're from Ohio, you're probably familiar with these pests. You probably know that for the next 4-6 weeks, they will stage a hostile takeover of our town, entirely covering our sidewalks, trees, and roads. There are actually reported cases of cicadas causing car accidents by swarming the vehicle, mistaking the engine for a particularly attractive-sounding mate.
Sure, we see a smattering of annual cicadas every summertime, but the onslaught we're currently experiencing is a whole different species called periodical cicadas, or 17-year cicadas, and they emerge every -you guessed it- 17 years. Among this species, there are separate broods, each specific to a certain geographical area. The brood plaguing Athens right now is called Brood V.
Brood V claims everything east of Columbus, except for a small bubble east of Cleveland. But don't worry, that bubble is partially covered by a different brood. In total, Ohio is home to four different broods of cicadas that all emerge at different times, meaning every 2-4 years, some part of Ohio is covered in ugly, noisy, crunchy pests. The map below shows which brood inhabits which area and when they will emerge next.
So we know what they are, and where they are, but one thing is still unclear: why is this even a thing? Why would any species spend 98% of its life underground, emerge to annoy the humans, and then die? It sounds like a painfully boring life, and it probably is, but it's also one of the most effective evolutionary strategies in the insect kingdom.
The cicada's main predators are birds, rodents, and pets, so living underground for 17 years ensures their survival for that long at least. But eventually they have to surface, molt their old exoskeleton and start gettin' it on to keep the brood going strong. This exposes them to their predators for the first time, but in all honesty, there are so many of them, it just doesn't matter. Their predators will eat as many cicadas as they can, but they quickly become too full to do any real damage to the cicada population.
But wait! There's more! By emerging together as a massive swarm, they throw off the ecological balance in the area. Their predators (specifically the birds) have a sudden increase in food supply, so they live longer and have more little bird babies, causing an unsustainable spike in population. The issue is, the cicadas are only around for a month or two, so by the time the baby birds hatch, there isn't enough food for the previously existing bird population, let alone for this sudden influx of newbies. This wreaks havoc on the bird world, and their numbers slowly dwindle. Any guesses on how long it takes for the bird population to reach its lowest point?
That's right: 17 years.
