Cicada Mania

Dedicated to cicadas, the most amazing insects in the world.

May 24, 2014

Cicada Myths

Filed under: Anatomy | Periodical — Dan @ 12:49 pm

Busting Cicada Myths

There are many myths (widely held but false beliefs or ideas) about cicadas. Time to bust some cicada myths.

Myth 1: Cicadas are sleeping when they are underground.

There’s a popular meme that [mis]states the following “if cicadas can sleep for 17 years and then wake up only to scream and reproduce so can i”. The actual tweet doesn’t say “reproduce”, but I want to keep it clean.

American periodical cicadas aren’t sleeping the entire 17 years they’re underground. Much of the time they’re digging tunnels and building feeding cells, tapping into roots and feeding, vying with other cicadas for space along a crowded root system, growing (they experience four phases or instars while underground), avoiding unfavorable conditions like flooding, and possibly actively avoiding predators like moles and voles. Yes, cicadas can sleep — or at least the insect version of sleep called torpor — but they are definitely not asleep for 17 years.

That said cicadas do spend their time screaming (the males) and procreating once above ground.

Myth 2: All cicadas have a 17 year life cycle.

This is false. Only three species, out of the thousands of cicada species in the world, have a 17-year life cycle: Magicicada septendecim, Magicicada cassini, and Magicicada septendecula.

Myth 3: All cicadas have periodical life cycles and synchronized emergences.

This is false. Only seven species in the United States (belonging to the genus Magicicada), and a few species in Asia (belonging to the genus Chremistica 1) have been confirmed to have periodical life cycles and synchronized emergences.

All other species of cicadas emerge annually, although in some years they are more plentiful than in others.

Myth 4: All cicadas live a prime number of years.

Many cicadas live a prime number of years, but some do not. Chremistica ribhoi, the World Cup cicada, has four year life cycle.

Myth 5: A long, periodical, prime number life cycle has allowed American periodical cicadas to avoid gaining a predator.

American periodical cicadas have avoided gaining an animal predator that specifically predates them, but they haven’t avoided a fungus. Massospora cicadina is a fungal parasite of Magicicada cicadas.

Male Magicicada septendecim infected with Massospora cicadina fungus

That said, just about any animal will eat an American periodical cicada, so they definitely get eaten. They get eaten a lot.

Myth 6: Cicadas make their well-known sound by stridulation, like crickets, grasshoppers & katydids.

It is true that some cicadas can make noise by stridulation, making sound by rubbing body parts.

However, and this is a huge “however”, the sound cicadas are known for is made by organs found in male cicadas called tymbals. Tymbals are a pair of ribbed membranes, that produce the cicada’s sound when they are flexed in and out by muscles. The mechanism is like the popping sound made when the plastic of a soda pop bottle is flexed in and out.

Tymbal

Cicadas can also make sound by flicking or clapping their wings.

Myth 7: Cicadas eat vegetation.

This is false. Cicadas lack the mouthparts to chew and swallow vegetable matter. Your tomatoes are safe around cicadas. Rather than eating solid food, cicadas ingest xylem, which is a type of tree sap that cicadas drink through their straw-like mouthparts.

Myth 8: American periodical cicadas are locusts.

Cicadas are not locusts. Locusts are a form of grasshopper. People confuse cicadas with locusts because both insects aggregate in massive numbers.

This is an image of a locust:
Locust

Characteristic Locust Cicada
Order Orthoptera Hemiptera
Hind Legs Giant hind legs for jumping Hind legs about the same size as other legs; great for climbing and perching.
What they eat Everything green they can find to eat Xylem sap
They’re in your town All the plants in your town have been stripped bare Cool UFO movie soundtrack sounds during the day

9) If you see a W appear in a cicada’s wings it means there will be a war. If you see a P, there will be peace.

This is the most mythical of cicada myths and has no basis in fact. That said, here’s the W:

W in cicada wing

1 Hajong, S.R. 2013. Mass emergence of a cicada (homoptera: cicadidae) and its capture methods and consumption by villagers in the ri-bhoi district of Meghalaya. Department of Zoology, North-Eastern Hill University, Shillong — 793 022, Meghalaya, India.

10 Comments »

  1. Antoinette Walker says:

    Thanks for all the info, I love learning stuff about nature.

  2. Angelina Mayhorn says:

    I live in Delaware Newcastle county we hear them every year and i watch the cicada killers every summer they seem to have taken up residence in our backyard. Im always seeing them carrying a cicada to its its underground lair to be put to death once its larva are laid.never realized they are such a big thing!!

  3. Jerry says:

    You said they haven’t developed an animal predator, but a Cicada Killer (looks like a hornet but only harms cicadas) is an animal. (animal, vegetable, mineral)

    1. Dan says:

      Cicada Killers are predators of Neotibicen cicadas, which are a different type of cicada. Both Cicada Killers and Neotibicen cicadas are active in the Summer, typically after Magicicadas have spawned and died. It’s Magicicada that does not have a specific predator unless we count this fungus.

      Of course, everything eats Magicicada, so regardless the strategy doesn’t stop them from being eaten.

  4. Phil Johnson says:

    b
    |Fascinating. I had no idea. I live in CA, and have never heard/seen anything like a cicada; just the ubiquitous locust/grasshoppers in some places… “Course, with our rain problem, even those might find it hard to get by here…

  5. david emery says:

    Neat Dan, lots of anecdotal hoo-hah about!! We are trying to pin down the triggers for Aussies cicada cycles, but these are not fixed like Magis! More likely climate opportunists!

  6. Jan Furansowa says:

    Hello,
    Thank you for this new post.
    According to Michel Boulard, a periodical cicada (Abroma pumila) who lives in New Caledonia (Oceania) has a 3 year life cycle. (Boulard M., The Cicadas of Thailand, vol.1, p.65)

  7. jen says:

    love this! can’t wait for our brood (in ky) to sing to me!

  8. Suzanne McCain says:

    Good information…I live in the brood XXII Baton Rouge area!! They are getting louder every day

Leave a comment. Questions about plants or snakes are deleted.

Leave a Reply to Jan Furansowa Cancel reply

Your email address will not be published. Required fields are marked *

Cicada T-shirts