Cicadas are found all over the world, but we mainly know them as those chirping ‘crickets’ when we are on holiday in Southern Europe. Cicadas are also found in Belgium, but they are much smaller. We know one of them as the spittlebug, or the foam cicada, which leaves a layer of foam behind to protect itself against enemies.
Perhaps a little more special than the European variants are the magicicades, which only occur in the eastern United States and which, depending on the species, live in the ground for thirteen or seventeen years, until they emerge by the billions at a time at the end of April. come crawling to mate and lay eggs, a large-scale orgy that lasts a few weeks, after which the animals die.
From the Earth to the Moon 33 times
There are seven species of magicicades, which live in thirty different places ‘bread’, an English word for clutch. That’s it for one of those bread Sometimes it’s time to come out, it’s not unusual. Even the hatching of two such bread in the same year happens occasionally. But it is absolutely certain that the two largest (one in number, the other in geographical distribution) populations will hatch together this year: it only happens every 221 years (13 times 17 is 221). The last time was in 1803, the next time will logically not be until 2245.
A magicicade sheds its skin for the last time and becomes an adult. — © AP
It makes cicada expert John Cooley of the University of Connecticut speak of one “cicada-geddon”. Floyd Shockley of the Smithsonian Natoinal Museum of Natural History suspects so Bread XIII and Bread XIX together with more than a trillion (or a thousand billion). “If you were to put them all together, you would get a little train that reaches from the Earth to the moon 33 times,” he says in The New York Times.
Prime numbers
To what do the animals owe their special lifestyle? “Their life cycle of thirteen or seventeen years – not coincidentally two prime numbers – helps the magicicades escape from predators,” says entomologist Peter Berx. “If they hatched annually or biannually, they would cross predators with the same life cycle much more often. That chance is now much smaller, so the population can build up better.”
Still, plenty of predators will be looking forward to the arrival of the magicidades. Birds, reptiles, squirrels and small mammals such as moles like them raw. But the magicicades are so numerous that the predators cannot possibly eat them all.”
Thousands of molted magicicade nymph skins lie on the ground. — © Getty Images/iStockphoto
Chainsaw
The animals may already be thirteen or seventeen years old, but their time above ground is very limited. “They live for years under the roots of trees as a nymph, a juvenile stage in which the insects already resemble an adult but do not yet have wings,” says insect expert Berx. “Once they are ready, they emerge from the soil, climb up tree trunks and molt one last time into an adult. All they do is sing, mate and lay eggs in trees. They die out after four to six weeks. Then the new generation of nymphs hatches, and they burrow again for thirteen or seventeen years.”
The chirping creatures can cause a hellish noise, up to 110 decibels loud, comparable to the volume produced by a chainsaw. They would have known this, especially in the state of Illinois, where both populations occur. Brood XIII will also be available in Wisconsin, Iowa and Indiana. Brood XIX can be heard and seen in Iowa, Texas, South Carolina and Virginia, among others.
Apart from some noise pollution, humans have little to fear from the cidads, because the animals do not sting or bite. “And they hardly eat when they are adults, so they don’t eat crops. It is not at all comparable to a locust plague. And after a month they are all dead again,” Berx explains.
Tags: Extremely rare natural phenomenon largest cicada populations converge ground time years
-
