Tell some amazing facts about Jellyfish ?

Environmental stress may increase jellyfish swarms. Jellyfish are one of the very few creatures that can adapt to ocean dead zones, or zones where there is little oxygen and lots of pollution. There are over 400 marine dead zones in the world.

A group of jellyfish is called a bloom, swarm, or smack.

Jellyfish blooms near Japan can have over 500 million jellyfish, with each jellyfish the size of a refrigerator.

Jellyfish have been responsible for temporarily shutting down a nuclear power plant in Japan after becoming stuck in its cooling system. The Japanese called these jellyfish echizen kurage or, in English, Nomura’s jellyfish.

Jellyfish account for more than 10 times the weight of the annual fish catch around the world.

Approximately 150 million people annually are exposed to jellyfish around the globe. Around 200,000 people are stung each year in Florida and 500,000 around the Chesapeake Bay.

Many scientists believe that environmental stressors—including climate change, pollution, overharvesting of fish, and dams—have led to the proliferation of jellyfish.

Jellyfish are harvested for collagen, which is used in a variety ways, including treating rheumatoid arthritis.

In 2007, jellyfish blooms decimated Northern Ireland’s salmon farm killing more than 100,000 fish.

Jellyfish belong to the Phylum Cnidaria. All animals in this group are radially symmetrical. Other animals in this phylum include hydras, sea anemones, and corals.

In several parts of the world, jellyfish are considered a delicacy. For example, in Malaysia, people call them “music to the teeth.” Approximately several hundred metric tons of jellyfish a year are eaten at $15 a pound, making it a multimillion-dollar business. The most commonly eaten jellyfish is the Cannonball jellyfish.

An American tourist died in 2002 after being stung by the deadly Irukandji jellyfish off the waters of Australia’s Great Barrier Reef. This jellyfish is only the size of a thumbnail but can have three-feet-long tentacles. Most jellyfish have stingers on their tentacles, but the Irukandji jellyfish has stingers on its bell piece as well.

An adult jellyfish is named a “medusa” (plural “medusae”), after the Greek monster Medusa that had snake for hair.

In the 2008 movie Seven Pounds, the character Ben Smith, an IRS agent played by Will Smith, commits suicide by sharing his bathtub with a deadly jellyfish. The title refers to the “seven ponds” of flesh Will Smith gives to other people to make up for killing seven innocent people in a car accident.

Jellyfish digest their food quickly. It would be difficult to float if they had to carry around large amounts of food.

The venom in a single box jellyfish can kill 60 people.

Jellyfish kill more people than sharks do each year.

Different jellyfish have babies in different ways. Some jellyfish shoot eggs out of their mouth to be fertilized outside the body; others carry the eggs in their mouth until it develops enough to live on its own.

Most jellyfish have two basic life stages. In the first stage, they are called polyps and grow by making buds, like plants. The polyp then buds off a young jellyfish called an ephyra. After a few weeks, the ephyra becomes an adult jellyfish or medusa.

Jellyfish are made up of more than 95% water. If they are removed from the water, they collapse and die.

The box jellyfish is unique because it has 24 eyes, four parallel brains, and 60 anal regions. Two of its eyes can see color. It is also one of the animals in the world that has a 360-degree view of its surroundings Box jellyfish are not considered “true” jellyfish of the Scyphozoan class.

Jellyfish that stay near the sunlight at the water’s surface tend to be colorless. Jellyfish that swim deeper are often red, purple, green, yellow, and sometimes they may even have stripes.

A military robotic jellyfish has been created to go on search-and-rescue and survey missions. The silicone “Robojelly” uses hydrogen and oxygen for fuel as it swims, so its only “exhaust” is heat and water. Its muscles are made from shape-memory alloy, a metal invented by NASA that “remembers” its original shape.

The top of the jellyfish that looks like the top of a mushroom is called the bell.

Scientists place true jellyfish and box jellyfish into two different groups. True jellyfish are scyphozoans, meaning “bowl animals.” Box jellyfish are cubozoans, meaning “cube animals.” A true jellyfish’s bell is rounded, like a bowl. A box jellyfish bell has sides and rounded corners—shaped similar to a box.