As you may have guessed from our name and logo, we’re big fans of jellyfish. They are absolutely fascinating creates, and have existed in our waters for 500 million years, maybe more! That’s longer than dinosaurs, and makes them the oldest living multi-organ animal group that we know of.
Considering there isn’t much to them, they are super interesting research and we’ve learnt a lot from them and their ability to produce their own light, called bioluminescence. Come with us as we travel the world’s oceans to learn more facts about jellyfish.
- Despite their name, jellyfish are not fish at all, they actually belong to a group of animals called invertabrate, because they lack a backbone.
- Jellyfish are found all over the world in waters of varying depths, but the majority of them are found in our oceans. Freshwater jellyfish, such as the Craspedacusta sowerbyi, are much rarer than their marine counterparts, so consider yourself lucky if you spot some in a lake!
- They come in all shapes and sizes, from just 2 centimetres up to a whopping 2 metres! Some are clear or translucent, making them incredibly hard to see, whereas some are a dazzling combitnation of vibrant colours like pink, blue, purple and yellow.
- Some jellyfish’s tentacles can sting, and while most are harmless to humans, they can be highly poisonous and very painful, and even deadly to humans. Always be aware of your surroundings if you’re in water where jellyfish can be found, just to be on the safe side.
- A group of jellyfish is called a ‘fluther’, ‘school’, ‘smack’ or ‘swarm’! So if you hear someone say “Watch out for that fluther of jellyfish!”, you may want to get out of the water just in case! A large fluther of jellyfish can contain over 100,000!
- Some species of jellyfish can be bioluminescent, meaning they produce their own light. It can be an incredible site to see, especially at night!
- Jellyfish dont have a heart, brain, bones or eyes! They are 95% water, and are made up of three different layers. These are called the ‘epidermis’, the outer layer which contains the nerve net, the ‘mesoglea’, the middle layer which is thick and elastic like and the ‘gastrodermis’, which is the inner layer.
- Their mouth can be found right in the centre of their body, and it is used for eating, discarding waste, and propelling themselves along by squirting water out of it!
- Jellyfish can eat anything from fish, shrimp, crabs, tiny plants,planktonic organisms and even other jellyfish!
- They are also eaten themselves! Sea turtles love to gobble up jellyfish, and in some parts of the world humans do too! They are considered a delicacy in China and are also used in Chinese medicines.
- Some jellyfish can clone themselves! If you cut one in two, they can regenerate to create two entirely new jellyfish! Similarly, the ‘Turritopsis dohrnii’, or ‘immortal jellyfish’, can effectively live forever. When it becomes stressed it can actually grow younger, replaying it’s life in reverse and becoming a less mature phsyical state.
- Not all jellyfish have tentacles, but the ones that do often use them to trap and immobilise their prey.
- Unfortunately jellyfish don’t live that long, with lifespans ranging from a few hours to a year.
- The most poisonous jellyfish is the ‘chironex fleckeri’, or box jellyfish. Like a lot of the world’s most dangerous beings they can be found in Australia, and their tentacles can reach up to 10 ft long with each one covered in hundreds of thousands of venomous microscopic darts. Thankfully stings are often survived if correct treatment is sought after very quickly!
Jellyfish are definitely the closest things to aliens that we know of, and are likely to continue to exist for a very, very long time!
|Classification||Invertebrate (no backbone!)|
|Diet||Carnivore (crabs, small fish, plankton, eggs)|
|Weight||Up to 2kg|
|Top Speed||8km/h (propelling themselves by squirting water out of their mouth!)|
|Habitat||Oceans and some fresh water|
|Conservation Status||Least Concern|