The song of the cicadas is a fable
Audio 02:32
The moult of a gray cicada.
© Wikipedia Commons
By: Florent Guignard Follow
7 mins
We hear it much more than we see it: the cicada is the insect of summer, the soundtrack of holidays in the south of France.
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Cicadas are the sound of summer in the south of France.
But the cicadas don't sing.
The insect has several lives and is sometimes better endowed than the ant.
"The cicada, having sung / All summer ..." ""
The cicada and the ant
"is one of the most famous fables of Jean de La Fontaine, but it is false! The cicadas sing? It is a big misunderstanding.
"
In reality, there is no vocal cord in insects, so there is no real talking about song
", underlines Stéphane Puissant, entomologist and in charge of conservation at the Museum Jardin des Sciences of the city of Dijon .
The cicadas rather play cymbals.
It is said that they cymbalize, thanks to the two cymbals, two membranes, placed on their abdomen that a powerful muscle deforms, to produce an overpowering sound.
"
It's as noisy as a Boeing taking off
," continues Stéphane Puissant.
Mainly the choirs when the sound emission of many males will synchronize. Sound power can reach and even exceed 100
decibels. The sound is diffused by the eardrums and the cicadas hear nothing. We can observe micro-cuts: cicadas stop to hear their fellows and assess the distance at which they stand.
The females in this case.
In cicadas, only the male is heard, to attract the beautiful precisely.
Well, beautiful, he doesn't really know anything about it.
“By gently approaching the thumb of a male transmitter, who is cymbalizing, he will tend to mate with your thumb.
This shows that he does not have a very good shape assessment.
"
Years of underground life
"The cicada, having sung / All summer / Found himself very destitute / When the north wind came ..."
Another failure, Jeannot!
You may hear cicadas all summer long, but an adult cicada only lives for one to two weeks in the sun, before dying, after giving birth.
The cicadas therefore do not know the harsh seasons, at least in the open air.
Most of its time, the cicada spends it in total darkness, underground, as a larva, for years, 2 to 6 years for gray cicadas, those we hear in the south of the France and in the Mediterranean basin, and even 17 years for periodic cicadas in the United States.
This is where they protect themselves from predators and build up strength to later transform into adults, feeding on the sap of plants that they bite at the roots.
The fabulist storytelling
"She went to cry famine / At her neighbor's ant / Asking her to lend her /
Some grain to subsist / Until the new season ... ”
Decidedly, the poet is not an entomologist;
the fabulist is a storyteller.
"Cicadas are better equipped than ants to get through the winter,"
explains Stéphane Puissant.
The juveniles, therefore underground, are able to move in the soil, to isolate themselves and to seek the roots deeply to feed themselves.
And the forban, in the story, is the ant: in summer, you have ants that arrive and come to take advantage of the sap that the cicadas extract.
"
The ant is not a lender, it is even a thief, even a killer, by eating juvenile cicadas when they come out of the ground before their transformation into adults.
This is another fable by La Fontaine: "
The wolf and the lamb
..."
"Is the sunflower spinning?"
"
The plant is aptly named.
The sunflower stems, and the leaves, indeed follow the movement of the sun, the nourishing light, to gain the maximum amount of energy via photosynthesis.
A growth gain estimated at 10%.
But once the flower opens, you no longer need to turn.
On the contrary, placed in the direction of the east and the rising sun, the flowers thus attract more pollinating insects.
Yes, plants always look to the sun.
A bit like humans at the moment on the beaches.
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