Our world is filled with creatures of all kinds who are fascinating but at the same time dangerous. Dolphins sleep with one eye open, penguins are birds but are flightless and then there are seals that can hold their breath for 2 hours. Like all the creatures I’ve mentioned here, Jellyfish is one of the most fascinating animals you will ever hear of: they are scary, brainless, and beautiful.
Jellyfish are mainly free-swimming marine animals with umbrella-shaped bells and trailing tentacles, although a few are not mobile, being anchored to the seabed by stalks. However, despite their name, jellyfish aren’t actually fish—they’re invertebrates or animals with no backbones.
The tentacles are armed with stinging cells and may be used to capture prey and defend against predators. They have a complex life cycle; the medusa is normally the sexual phase, the planula larva can disperse widely and is followed by a sedentary polyp phase.
Jellyfish have drifted along on ocean currents for millions of years, even before dinosaurs lived on the Earth. The jellylike creatures pulse along on ocean currents and are abundant in cold and warm ocean water, in deep water, and along coastlines.
Annette Govindarajan, a Lecturer in Northeastern University’s Department of Earth and Environmental Sciences, was interested in how large blooms of jellyfish form in the ocean. She said reports of these blooms are increasing in different parts of the world, and they often happen in polluted waters where algae have died and decomposed.
However, there are many other facts which makes a jellyfish a really interesting animal. Some of them are-
A Jellyfish has no eyes, no brain and no heart.
They are mostly comprised of water, that is 95%.
A group of jellyfish is known as a bloom.
Some jellyfish are also bioluminescent; that is they can emit light.
Jellyfish are also harvested for their collagen, which is being investigated for use in a variety of applications including the treatment of rheumatoid arthritis.
Jellyfish in large quantities can fill and split fishing nets and crush captured fish. They can clog cooling equipment, disabling power stations in several countries; jellyfish caused a cascading blackout in the Philippines in 1999.