They’ve been asleep for seventeen years, but they’re getting ready for a mad dash to find a mate
Lesson summary
Hi there, thanks for joining us for Plain English lesson number 364. I’m Jeff; JR is the producer; and the full lesson, including the transcript, is available online at PlainEnglish.com/364.
Coming up today: Have you heard the expression “a force of nature”? The cicadas are a perfect example of a force of nature. These guys have lived underground for 17 years and they’re about to come out from underground for just a few weeks before they die. And there will be trillions of them. Today’s lesson is all about Brood X of the periodic cicadas. The expression is “live on” and we have a quote of the week.
Cicadas prepare to emerge after 17 years
A passage in the Bible’s Old Testament describes how locusts covered the earth and devoured all the fields in Egypt. What’s coming in 2021 is not quite on that level, but Americans in 15 states are getting ready for Brood X, a cohort of trillions of loud cicadas that come out just once every seventeen years.
The cicadas are one of nature’s mysteries: These thumb-sized insects spend exactly seventeen years silently developing underground, and then they emerge all at the same time. Once they are above ground, they scramble to mate together—and then they die just as quickly as they arrived on the scene. After just a few weeks, it’s all over: a new generation of cicadas is buried in the ground and the countdown begins again.
The life of a cicada goes like this. They hatch from eggs and immediately dive underground. They stay about eight inches below the surface, living on the sugar from tree roots. After seventeen winters, they start to get ready to come to the surface. When the soil temperature starts to warm up, they begin to dig tunnels up toward the surface. When the soil temperature reaches 64 degrees Fahrenheit, they come out from underground.
That’s when the real action begins. The cicadas then shed their skin and sprout wings. The male cicadas perch high on trees and produce their mating call. Once they mate, the females lay eggs. Both the males and females die just days later. That’s it: that’s their whole life above the surface. Almost seventeen years underground, all in preparation for a couple of weeks of action. New cicadas hatch from the eggs and then tunnel into the ground and the cycle repeats.
Cicadas live in broods: cohorts that all live and die on the same seventeen-year cycle. Large parts of the eastern United States are home to cicadas, but not every brood is on the same cycle. So in almost any given year, some part of the US will experience cicadas. However, Brood X is the biggest and most intense. And they are getting ready to come out this year.
When they do, they will blanket the areas in which they live. There will be millions per acre in some areas. They will cling to trees and houses. There will be trillions in total.
Unlike the locusts that destroyed the crops in Egypt in Biblical times—and unlike the modern-day locusts that still plague Africa —the cicadas are not harmful either to humans or to crops. The worst they’ll do is damage a few trees. But trillions of these cicadas will make an ear-splitting noise, 24 hours a day, for several weeks. Each male can sound as loud as a lawnmower. For humans in most areas, the sound of the cicadas is like listening to a jackhammer coming from all directions: you can’t escape it unless you find a place with no trees. Two people standing next to each other would have to shout to be heard over all the racket. The noise is the mating call: males, high above the ground, emit the loud sounds as they hope to attract a mate.
A cicada is about the size of a human thumb. They have black bodies, bright red eyes, and orange-striped wings. Nobody knows how cicadas can count the seventeen years in their cycle. Scientists speculate that their emergence is either regulated by hormones or by the nutrients in the trees, but it remains a mystery. (Some cicadas are on a thirteen-year cycle, but the majority are on the longer seventeen-year cycle.)
Another mystery is why they all emerge at once. Scientists suspect this gives the cicada an evolutionary advantage. Snakes and birds would be the most natural predators, and some do indeed feast on the cicadas. But the cicadas come out in massive quantities, so even the hungriest predator can’t do any real damage to the brood as a whole.
Cicadas don’t bite and they present no harm to humans or any other animals. They don’t even affect crops. They mostly suck fluids from tree and shrub branches, but even this doesn’t harm trees.
The only damage they do is to the trees in which they lay eggs. Females have a small built-in saw that they use to dig a ridge into twigs and tree branches. They cut a groove into the branch and deposit their eggs in there. Some trees can be damaged from all the cicadas cutting into their branches at once, so landscapers sometimes cover their trees in netting. Cicadas prefer oak, maple, and fruit trees; they leave the evergreens mostly alone.
The parents die before ever seeing their offspring hatch. The eggs hatch into nymphs, which fall to the ground and dig into the soil. The next emergence of Brood X will come in 2038.
Dripping cicadas
I lived in Ohio during the last cicada cycle, in the summer of 2004. That was one of the most intense areas for Brood X. Believe me when I tell you, if you were outside in an area with trees, you would have to shout at someone standing just a few feet away from you. That’s while they’re alive.
The really gross thing is when they die. They fall from the trees. You can be walking down a sidewalk and dead cicadas will just drop from the trees on top of you; they crunch underfoot as you walk. They get in your hair. They get in your clothes. They fall or fly into open car windows. For months, maybe even years, I was finding dead cicadas in the small nooks and crannies of my car.
They’re coming out again soon. They won’t be where I live now, but I might go to Indiana, the next state over, just to hear them when they’re in full force . I’ll keep my car windows closed, though!
I read a story about a woman who had planned an outdoor wedding in a well-landscaped area, right for the middle of cicada season, without knowing it. Talk about bad timing!
Great stories make learning English fun
