(Contenido disponible en Español está marcado abajo)
Have you ever wondered what animal was making the noise we often hear in the summer in Chicago? It’s a cicada. Cicadas are strange-looking insects that can measure up to 2.25 inches long. Despite their kind of small size, they can make a lot of noise! Let’s learn more about these cool critters.
Cicada nymphs on the move
Cicadas go through metamorphosis just like butterflies. They spend a long time underground as nymphs. When they’re ready to molt and become an adult, they emerge from the ground, and find a tree or sturdy spot to hang from. Watch this video from Samuel Orr to learn more about the cicada life cycle.
Guiding Question: How is the cicada life cycle the same as butterflies? How is it different? Do you know of any other animals that go through metamorphosis?
Annual vs periodical cicadas
Not all cicadas emerge at the same time. Some, called annual cicadas, emerge every year. In Chicago, those are the green and brown ones that we see most often. Others, called periodical cicadas, only emerge every 13 or 17 years. The cicada pictured here is a periodical cicada. Bug expert Allen described some more differences between them in a recent interview. Click here to listen to it.
Guiding Question: Compare this photo of a periodical cicada to the photos above and below of annual cicadas. How are they similar? How are they different?
How do cicadas make sound?
Cicadas have a special organ called a tymbal that produces sound. The tymbal contains a series of ribs that buckle one after the other when the cicada flexes its muscles. Every time a rib buckles, it produces a click. Many clicks produce a buzzing sound. It’s similar to how a bendy straw makes sound: pulling and pushing the ribs of the bendy straw together makes a series of clicks. If you could push, pull, and twist a bendy straw hundreds of times a second the sound of the clicks would be so close together that you’d only hear a buzzing sound. Click here to check out our full blog post on cicada sound.
Make a cicada
(Disponible en español)
Make your own cool, colorful cicada by checking out this how-to origami video. All you need is a square piece of paper!
Teaching Tip: Keep exploring about bugs by checking out “Bug Parts” by Charlotte Guillain. Click here to view it in English and here to view it in Spanish.
Cicadas and community science
Cicadas are pretty important insects. They can help scientists learn about the changing environment. You can help scientists at the University of Tennessee in Chattanooga collect data by participating in this community science project.