There's no denying it – jellyfish are weird animals. They look weird, they swim weird, and some even glow in the dark. Did you know that World Jellyfish Day is on November 3? Get your tentacles ready to learn about these awesome ocean creatures!
Jellyfish come in many shapes and sizes. The smallest can only be seen with a microscope. The largest, the lion's mane jellyfish, can grow up to 120 metres long! Watch out! Lots of jellyfish have tentacles that sting their prey to stop it from moving. Some mild jellyfish stings can cause rashes and welts on humans. More severe stings can be deadly. Box jellyfish, which mostly live in tropical waters, are considered by scientists to be the most dangerous marine animals.
Some fun facts about jellyfish: 
One important fact to get straight is that jellyfish aren't fish. They are actually a kind of plankton. Some jellyfish can swim, but some just float along, eating whatever comes their way. Unlike humans, jellyfish are invertebrates, which means they don't have spines. They also don't have brains. Some jellyfish have eyes, and some even work similarly to human eyes. Others only sense light and shapes. Box jellyfish can have up to 24 eyes! Humans have been on Earth for about 300,000 years. Jellyfish, on the other hand, have been around for 500 million years. Yes, you read that right – more than 250 million years BEFORE the dinosaurs, according to the Orlando Science Centre.
If you're looking for ways to celebrate this World Jellyfish Day, consider checking out some of these stingingly good books from your local library!
The Box Jellyfish by Laura L. Sullivan
Deadliest! by Steve Jenkins
Jellyfish by Ann Herriges
Jellyfish by Judy Wearing
Jellyfish! by Ginjer L. Clarke
The Not Bad Animals by Sophie Corrigan
