- Name: Jellyfish
- Subphylum: Medusozoa
- Number of Jellyfish Species: 2,000+
- Range: Worldwide (marine and freshwater)
- Diet: Carnivorous
- Size: Between .04 inches and 6.6 feet
20 Jellyfish Facts for Kids
- There are over two thousand species of jellyfish around the world.
- Jellyfish are estimated to be older than the first dinosaurs.
- Jellyfish are invertebrates, which means they aren’t fish.
- Jellyfish can be clear (translucent) or have a vibrant array of one or more colors.
- Some jellyfish are bioluminescent, which means they can produce their own light.
- Jellyfish can be as small as .04 inch and as big as 6.6 feet.
- Jellyfish don’t have a brain, bones, eyes or a heart.
- A jellyfish’s body is 95% water. The other 5% is structural proteins, muscles, and nerve cells.
- Jellyfish are marine (saltwater) animals, but a few can tolerate and be found in freshwater.
- Jellyfish are carnivorous and eat crabs, fish, shrimp, tiny plants and other marine based animals.
- Jellyfish use their tentacles to stun or paralyze their prey prior to eating it.
- A jellyfish uses its mouth to eat food, discard waste and squirt out water to propel itself.
- A group of jellyfish can be referred to as a bloom, smack or swarm.
- Groups of jellyfish can contain over 100,000 of them.
- The immortal jellyfish (Turritopsis dohrnii) is estimated to be immortal and have an infinite lifespan.
- Jellyfish pose a great danger to humans. They don’t purposefully attack humans, usually it’s by accident when someone swims near one and touches it on accident.
- A sting from a jellyfish’s tentacle can result in massive amounts of pain, scarring and even cause death.
- The Chironex fleckeri, also called the sea wasp, is one of the most lethal jellyfish to humans
- The box jellyfish, a group of 51 known species, is estimated to be the most venomous marine animals on our planet.
- It’s a myth that urinating on a jellyfish sting will relieve the pain. One way to alleviate the pain from a sting is to remove the tentacles with tweezers and soak the area stung in hot water.
Pictures of Jellyfish Species
A photo of a Compass jellyfish.
Credit: Tim Gray
A photo of a Cyanea jellyfish.
A photo of a Sea Nettle jellyfish
Credit: Jim G / Flickr
Additional Resources on Jellyfish
- What are jellyfish made of? – Discover what jellyfish are made out of on the NOAA website.
- Jellyfish – Wikipedia – Learn more about jellyfish and the different species of jellyfish on the Wikipedia website.
- Jellyfish – National Geographic Kids – Discover more jellyfish facts for kids on the National Geographic Kids website.