- Jellyfish are about 98 percent water. If a jellyfish washes up on the beach, it will mostly disappear as the water evaporates.
- If you cut a jellyfish in half at any point, you'll always get equal halves.
- Jellyfish don’t have any brain, heart, or bones. They react directly on food and danger stimuli via nerve impulses without having any brain to process the impulses.
- A species of jellyfish, the Box jellyfish (sea wasp) kills more people than any other marine creature each year.