With all the awkward shapes and colours, jellyfish is one of those interesting creatures who we want to know more about.
1. Old, really old
Imagine being even older than dinosaurs! That’s exactly what jellyfish are. They’ve been around for millions of years, since before dinosaurs roamed Earth. Some scientists believe that they’ve been around for more than 500 million years. In fact, they’re the oldest multi-organ creature on our planet.
2. Immortal
Not only are they the oldest, but at least one species of jellyfish, the Turritopsis nutricula, known as the ‘immortal jellyfish’, is believed to be… well, immortal. This jellyfish can renew his cells and thereby ‘cheat’ death.
3. Not a fish
We’ve always known them as jellyfish, but scientists prefer to refer to them as jellies or sea jellies and don’t classify them as fish. Jellies are considered to be plankton and are related to sea anemones and corals.
4. Glow in the dark
Jellies can produce their own light and use this as a defense mechanism or to attack their prey. The colours are vibrant and make them look like they’re glowing in the dark. This tactic is used to either startle or distract other creatures. Some jellies can let go of a glowing tentacle or particles to confuse predators. Others are transparent (see-through), and some can be pink, blue, yellow or even purple.
5. Brainless creature
Jellies don’t have a head with a brain like most animals. Instead, they have a network of nerves to control functions in their bodies, like feeling temperature or knowing when they are in danger. The network of nerves runs throughout the jellies’ bodies.
6. Body composition
Besides missing a brain, jellies also don’t have hearts, eyes or even bones. These creatures have a body that looks like a bag and is smooth, and tentacles that have tiny stinging cells to stun or paralyse their prey. They do have a mouth that is in the middle of the body, which is used to gulp down their food.
7. Jellyfish stings
Not all jelly stings are poisonous but, because you might not know which kind of jelly stung you, you’d be better off getting medical attention as soon as possible. Most jelly stings only cause minor irritation – pain, red marks, itchiness, numbness or tingling – but are not life-threatening.
