The spectacular life of the jellyfish
Dive into an undiscovered world
Among the most extraordinary animals on earth, jellyfish (Cnidarians,
scyphozoans, cubozoans, and hydrozoans) are also some of the most
ancient, with an evolutionary history stretching back for hundreds of
millions of years. Found in all oceans of the world, jellies are made up
of 90 to 95 percent water, compared to 60 percent for humans. Jellyfish
come in a wide variety of shapes and sizes. The largest is the lion's
mane jellyfish (Cyanea capillata), which can have a bell over six and a
half feet in diameter and weigh up to 440 pounds; the smallest is the
Irukandji jellyfish, several species of dangerous jellyfishes found in
tropical waters, which measure only about two-tenths of an inch and
weigh well under a tenth of an ounce.
Jellyfish have no brain, heart, bones or eyes. They are made up of a
smooth, bag-like body and tentacles armed with tiny, stinging cells.
These incredible invertebrates use their stinging tentacles to stun or
paralyse prey before gobbling it up. The jellyfish’s mouth is found in
the centre of its body. From this small opening it both eats and
discards waste. And it serves another purpose, too – by squirting a
jet of water from its mouth, the jellyfish can propel forward!
Cool, eh?
Jellyfish digest their food, which consists of fish, shrimp, crabs and tiny plants, very quickly. If they didn’t, they wouldn’t be able to float, being weighed down by the large, undigested grub in their body. The jellyfish itself provides a tasty meal for other ocean creatures, particularly sea turtles, who like to guzzle them up regularly. In some cultures around the world, people eat jellyfish, too. Jellyfish stings can be painful to humans and, from certain species, they can even be deadly. Although these magnificent marine creatures don’t purposely attack humans, most stings occur when people accidentally touch a jellyfish.
👉 Learn more about the uniqueness of jellyfish here!
This page was built by Imke