Jammin’ Jellyfish

A Panoply 2015 Community Art Interactive

Have you ever seen jellyfish swim at the aquarium? How do they do that? Jellyfish don’t seem to have any bones or muscles, so how do they move?

Jellyfish use a jet propulsion system to move through water. Cup your hand like you are about to pick up a ball. Now close your fingers. The air space inside your palm area just got smaller. The squeezing motion and air in that area is the same motion that jellyfish use to squeeze their bodies to push jets of water below them to propel their bodies forward in the water. The part of the jellyfish that looks like a ball is called a “bell.” The bell collects water, squeezes, and then pushes water out.

Some larger jellyfish don’t have bells that can squeeze tightly and therefore cannot push a large amount of water for movement. Their bells are wider and move in a rowing motion instead. Larger jellyfish cannot move up and down as easily as smaller ones.

Jellyfish also use ocean currents to move in the water. The jet propulsion system moves them up and down, but the current moves them from side to side. Therefore, jellyfish can’t really decide where they are going. They depend on the ocean’s movement most of the time. CLICK HERE to read more about how a jellyfish works.


1. Jellyfish have been around for over 500 million years, even before dinosaurs!
2. Many jellyfish are transparent (see-through)
3. Jellyfish are not fish
4. Jellyfish do not have brains, blood or nervous system
5. Jellyfish travel is groups called blooms that can be as large as 1,000,000
6. Jellyfish eat shrimp, crab and tiny plants
7. Jellyfish sting their prey. Sometimes humans are stung by jellyfish and some species are harmful to humans
8. There are thousands of different Jellyfish species
9. The lifespan of a jellyfish is anywhere from 2 months to 1 year
10. Jellyfish are kept in round aquariums to prevent them from getting stuck in the corners

There are many different shapes and sizes and colors of jellyfish. The colors of different species of jellyfish depend on the pigments of the microorganisms living inside of them. Most jellyfish are translucent, or “see-through” – but the things that they eat are not translucent. Therefore, they appear to be the color of the things that they eat. “You are what you eat.”
National Geographic video
Swim with millions of golden jellyfish