Tell some amazing facts about Jellyfish ?

There exists a type of jellyfish that resembles a plant. It lies on the seabed upside down.This way it collects energy from the sun.

The quantity of venom found in Box Jellyfish is capable of killing 60 people.

More people are killed by jellyfish each year than by sharks.

Rainy season decreases jellyfish population because jellyfish can only survive in salty water.

The jellyfish are grouped under Cnidarian phylum, whose characteristic feature is the presence of a gelatinous and a non-living body embedded between the epithelial layers. There are around 2000 different types of jellyfish and scientists say that 3000000 different species of jellies are yet to be discovered.

Jellyfish come in a diverse range of forms and colors like pink, white, yellow, orange, green, and blue. Some are even multi-colored. Jellyfish are composed of 90% water. Most of their body is a gelatinous material called mesoglea surrounded by two layers of cells that form the umbrella. The subumbrella of the body is called the bell.

Jellyfish do not have a respiratory system, as their skin is thin enough to oxygenate the body by diffusion. Neither do they have central nervous system or brain. Rather, they have a loose network of nerves (nerve net) located in the epidermis. This nerve net helps them sense the changes in their environment and coordinate the marine animal’s responses.

The mouth of the jellyfish is housed in a dome or bell-shaped central body area surrounded by tentacles. They discard and eat the waste from this mouth-like opening. They even squirt water from their mouth, which propels them forwards.

The movement of jellyfish depends on the currents and tide of the water and wind. Some jellyfish are sensitive to light and move downwards during the daytime. Jellies also need water for survival. The absence of water can cause desiccation and death of these marine creatures.

Jellyfish have stinging cells in the tentacles, which are filled with toxins. They stun or paralyze their prey before eating them. Jellyfish typically don’t attack humans. Most of the stings occur when humans accidentally touch a jellyfish. But, some species of jellyfish can be fatal for humans. Jellyfish washed ashore can also sting. Be very careful if you are investigating a specimen. A tentacle separated from its body can sting and carries enough venom to be fatal.

Jellyfish are dioecious. So a jellyfish colony will either be entirely female or male. And in most of cases, both male and female jellyfish release eggs and sperm into the surrounding water where the eggs fertilize and mature into new organisms.

The box jellyfish is the deadliest animal in the animal kingdom. It has caused 5568 deaths since 1954. Each tentacle of the box jellyfish has around 500000 sindasites, harpoon-shaped needles that inject venom into the victim. The venom can lead to a 4 to 10-year-old child’s death within 3 minutes.

The Arctic Lion’s Mane is the largest species of the jellyfish. The Arctic Lion’s Mane jellyfish is one of the longest known marine animals. The diameter of the body of Arctic Lion’s Mane is 7 feet 6 inches. And the tentacles are around 120 feet long. An Arctic Lion’s Mane was found washed up on the Massachusetts Bay shore in 1870.

The Portuguese Man-of-Wars can grow up to 50 meters long. On a baseball diamond, these jellyfish would reach more than halfway to second and from home plate to first base. You’ll find these jellyfish mostly in groups, floating in warm ocean waters. To avoid the threats, Portuguese Man-of-Wars deflate their air bladder and sink briefly under the water.

Creeping Jellyfish, belonging to the Staurocladia, is the smallest species of jellies. It has 0.5mm bells discs with tiny tentacles that stretch out a bit further. These jellies crawl at the base of the ocean, and you cannot see them without a hand lens or microscope.

When the conditions are good, that is the perfect temperature and plenty of food, jellyfish can grow extremely fast and reach high numbers. It’s a part of the natural seasonal cycle of the jellyfish species.

Jellyfish dine on different things like fish eggs, copepods, shrimp, small plants and other small fish called larvae. They eat the planktonic eggs at the younger stages. Some jellyfish also eat other jellyfish! When the jellyfish blooms, they eat almost everything in the water, which often cause problems for the fisheries because of the lack of food.

Jellyfish have a strong digestive system. They digest the food extremely fast. That’s because they wouldn’t be able to float if they carried digested meal around.

Moon Jellyfish is the friendliest species of jellyfish. These jellyfish also sting, but the effects are mild and short-term.

Moon Jellyfish is the most common species of jellyfish. You’ll find this species of jellyfish mostly in the aquariums. But since they are minuscule species of jellyfish, they do not survive for more than six months in the natural habitat. The factors responsible for the death of Moon Jellyfish are warm temperature, lack of food and diseases. They live for several years in the controlled conditions of the aquariums, where there is no predator or competition for food.

Nonpoisonous jellyfish are considered a delicacy in many parts of the world. Around several hundred metric tons of jellyfish are eaten every year at $15 a pound, making it a multi-million dollar business. The Cannonball Jellyfish is the most commonly eaten jellyfish.

It has been reported that jellyfish blooms are responsible for shutting down nuclear reactors, most of which rely on ocean water intake. The swarms of the jellyfish clog intake pipes, forcing many facilities to cease operations temporarily.

Just like most animals, even the jellyfish has a life cycle. The most familiar stage is the medusa stage where jellies swim around with their tentacles hanging down. Male and female medusa then reproduce and form thousands of tiny larvae called planulae. The larvae settle on the bottom of the ocean and form small polyps that look just like little small Anemone. The polyp bud off baby jellyfish called the ephyrae that grow quickly into an adult medusa.

The lifespan of jellies is 30 years. Some jellyfish live less than a year while the smallest one lives just for a few hours. The size and lifespan depend on the species. But on an average, most jellyfish live for 2 to 6 months.

Some of the jellies make their light. They have bioluminescent organs that help them emit light. These jellies use this light to distract predators and attract prey.