Facts about jellyfish (aka Sea Jellies)

The JellyFish Life

1. Classification: Invertebrate

2. Scientific name: Turritopsis

3. Jellyfish have been around for longer than dinosaurs, for +500 million years

4. They come in all sizes, shapes and colours.

5. Life Span: the average jellyfish lives about one year (in the wild)

Huh? I thought they were immortal? 
Well... yes and no. They do regenerate and like the ‘immortal jellyfish’, go back to its blob-like polyp stage after reproducing. They can start over again when they get ill, when they are being starved or lose parts of their body, but usually they get eaten or ill before they can get very old. When they are in their polyp stage, they are prone to diseases and to predators who see them as a tasty meal. So simply said, they could be immortal if they wouldn’t get eaten or become ill in their polyp stage...

For example the Moon jellyfish is known to live around 12 to 18 months, but in the “perfect” living conditions could live up to an age of 20 years old. On the other hand, some other types of jellyfish don’t become much older than a couple of hours. So depending on the species and the environment they live in, they can live from a few hours up to a year and a half.

The JellyFish Life

6. Weight: Up to 2 kg (4.4 lbs)

7. Top Speed: 8 km/h (5 mi/h)

8. Diet: Fish, shrimp, crabs, tiny plants and other species of jellyfish

9. Habitat: Oceans (Mediterranean and Japan mainly, but you can find them in Oceans all around the world)

10. Jellyfish have no brain, heart, bones, blood or eyes, but hey! You can’t have it all :)

No brain? How do they function then?
Ha! Here’s the fascinating thing. They don’t have a brain, but instead, they have a system of nerves at the base of their tentacles that reacts to stimuli like touches or temperature changes.

11. They live in colonies, or as solitary travellers.

12. Some have a sting that merely irritates, others have a more lethal sting.


(Looking at the last few bullet points, I think we know some people like that too, not just jellyfish... ;) )

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Read about 'The JellyFish Life' here.