Casey: Cicadas, the wedding crashers who can jitterbug
We are about to witness the largest insect emergence on the planet, and it happens only in the eastern United States. At the beginning of May, billions of Magicicada septendecim nymphs will start to rise out of the ground en masse, from North Carolina to New York, finding a tree (or the nearest vertical structure, possibly your house) to cling to. There, they will split their skins and emerge as adults.
The website for Cicada Mania has a map that gives a good idea of where and when the swarms will occur (earlier in the South) and answers questions. The most frequently asked question: Will cicadas ruin my wedding?
This is evidence, sad to say, of how incurious and self- centered we human beings can be. Yes, they look bizarre with their bulbous red eyes. Yes, the sound could interfere with the band at the reception.
But the event, and I don't mean the wedding, is very impressive. A week of body hardening and the males are ready to sing - a buzz of 80-90 decibels (about the same as a blow- dryer, kitchen blender, noisy playground or crowded bar). Then the insects have just a month of life, which the males spend mating many times, the females once. The resulting eggs - laid in twigs - then hatch before the infant nymphs fall to the ground and dig down a foot to wait for another 17 years. (The last brood appeared in 1996.)
Cicadas can't harm human beings, and they will be dead by the end of June. Brides and grooms, if you insist on June, you should think about a screened porch. Or consider that an outdoor June wedding could actually be enlivened by a few thousand cicadas (sometimes there are a million per acre).
The insects don't sting or bite, though they are very inept fliers and bump into people, which is either amusing or scream- inducing. Their black bodies trimmed in orange and veined wings would show up nicely on white tablecloths and pastel bridesmaids' dresses. They have no interest in human food, but might fall into the pasta salad.
The main point is, however, how about a little awe? It's a long time to wait to come up into the light. These insects spend 17 years as little wingless nymphs, feeding on tree roots - a dark and quiet life. Their only tasks are to grow bigger and bigger with successive molts, and to count. How, speaking of awe, do they count?
Some other creatures in the dark count warm seasons versus cold ones. The 17-year cicadas keep track of the years by the number of springs that the tree to which they are attached flowers. (Scientists once put some cicadas in a pot under a pear tree that was forced to bloom twice in a year. The insects' development accelerated.)
The first really risky thing in their lives occurs when the counting is over, the soil temperature rises to more than 65 degrees Fahrenheit, and they dig out, clamber up a tree trunk and shed their nymph exoskeletons. The covering is sticky so it's possible to lose an antenna or a leg, or get stuck halfway out and die before getting a chance to reproduce.
Once the luckier ones unpack themselves and unfold their crumpled wings, a matter of several hours, the cicadas can fly away, but they won't make noise for another week and then only, thankfully, in the daytime. The males congregate in choruses and the females, who don't sing, find their way to the ensemble where they will find a male and mate - end to end. Entomologists say they have no idea what the female is looking for and whether she is concerned with finding the fittest mate.
"She's looking for Mr. Good Enough," says Cole Gilbert, an associate professor of entomology at Cornell University. "Seems to me like she's not putting a lot of thought into this."
Not a lot of thought? She has had 17 years to dream of the perfect male. We know how they have slowly counted out the years, but why the long, long wait?
The survival strategy for the species is to swamp hungry predators. Birds, lizards, squirrels, raccoons, foxes, ants and spiders gorge themselves until they can't stand to look at another cicada. Any stragglers coming a year later, or a year earlier, in a smaller cohort would all be gobbled up. (Cicadas are easy to catch and satisfyingly crunchy.) The insects fit into the web of life by being food, and the masses of leftover dead bodies add a pulse of nitrogen to forest soil.
This has been going on for a lot longer than human beings have had wedding planners. (They should, by the way, have paid more attention to what year it was. Check those calendars for 2030.) About 4 million years ago, the strategic cicadas diverged from their brethren that didn't stay underground as long.
The buzzing, the being bumped into, the picking them off your gown, the insects in the salad - these seem paltry concerns in the big scheme of things. (And you could ask yourself some meaningful questions about your fellow human beings, such as, "Will a cicada get drunk and proposition my father's second wife?") These creatures have waited 17 years to mate; how hard would it be to delay your wedding a few weeks?
Constance Casey writes the Species column for Landscape Architecture Magazine and the series "Revolting Creatures" for Slate.