Fascinating Facts About Jellyfish, Part IV

Jellyfish fact: Jellyfish has been around for more than 650 million years which means that they outdate both dinosaurs and sharks.

Jellyfish fact: Different species of jellyfish can be found in all the worlds’ oceans. A type of jellyfish (that isn’t considered “true” jellyfish by science) can even be found in freshwater.

Jellyfish fact: A species of jellyfish, the Box jellyfish (sea wasp) kills more people than any other marine creature each year.

Jellyfish fact: The worlds largest known jellyfish can reach a diameter of 2.5 m / 8ft and its tentacles can grow to be half the length of a football field.

Jellyfish fact: Jellyfishes uses jet propulsion to make their way through to the oceans of the world. Some jellyfish are avid swimmers while other mostly drifts with the currents.

Jellyfish fact: Some species of jellyfish contains a lot of protein and are thought to be able to play a large role in ending hunger and malnutrition in poor areas around the world.

Jellyfish fact: Jellyfish are able to reproduce both sexually and asexually during different parts of their life cycle.

Ugly Gets Beautiful - Giant Jellyfish Swimming

Even the ugliest of ugly fish can be beautiful...well, I don't know about the Blob Sculpin...but the jellyfish sure is gorgeous and graceful.

Check out this video of a giant jellyfish gliding through the ocean:

Fascinating Facts About Jellyfish, Part III

The life cycle of a jellyfish:



In the reproductive life cycle of a typical jellyfish, males release sperm and females release eggs into the water. When an egg and sperm fuse to form a fertilized egg during sexual reproduction, a larva develops that attaches to a rock or other object and develops into a polyp. In a type of asexual reproduction, the polyp transforms into a colony of polyps that resembles a stack of saucers. Each saucer in the stack detaches itself from the colony as a new medusa, and the reproductive cycle repeats.

Depending on the species, a jellyfish has a lifespan of one month to one year, very few live longer than a year.

Fascinating Facts About Jellyfish, Part II

Jellyfish live mainly in the ocean, but they aren't actually fish -- they're plankton. These plants and animals either float in the water or possess such limited swimming powers that currents control their horizontal movements. Some plankton are microscopic, single-celled organisms, while others are several feet long. Jellyfish can range in size from less than an inch to nearly 7 feet long, with tentacles up to 100 feet long!

Jellyfish are about 98 percent water. If a jellyfish washes up on the beach, it will mostly disappear as the water evaporates. Most are transparent and bell-shaped. Their bodies have radial symmetry, which means that the body parts extend from a central point like the spokes on a wheel. If you cut a jellyfish in half at any point, you'll always get equal halves. Jellyfish have very simple bodies -- they don't have bones, a brain or a heart. To see light, detect smells and orient themselves, they have rudimentary sensory nerves at the base of their tentacles.


A jellyfish's body generally comprises six basic parts:

• The epidermis, which protects the inner organs
  
• The gastrodermis, which is the inner layer
  
• The mesoglea, or middle jelly, between the epidermis and gastrodermis
  
• The gastrovascular cavity, which functions as a gullet, stomach, and intestine all in one
  
• An orifice that functions as both the mouth and anus
  
• Tentacles that line the edge of the body

Fascinating Facts About Jellyfish, Part I

• Jellyfish don’t have any brain, heart, or bones. Some jellyfish have ways of detecting obstacles that can be compared to sight but they don’t have real eyes. It is a mystery how they can process the information from their “sight” since they doesn’t have any brain. They react directly on food and danger stimuli via nerve impulses without having any brain to process the impulses. Another fact about jellyfish and their bodies is that the body consists of over 95% water.
  
  Yup, the jellyfish is ugly, brainless, and heartless. Ouch!
  
  
• Jellyfish use tentacles with stinger cells to catch their prey, typically plankton and small fish. (The exact prey depends mainly on the size of the jellyfish.) The tentacles transport the prey they killed with their stingers to the mouth and the jellyfish promptly devours the animal. It is the same stinger cells that stings humans that ventures to close.
  
  
• Jellyfish are made up of an epidermis, gastrodermis and mesoglea. Jellyfish do not have a central nervous system,a circulatory system, respiratory system, or a osmoregulatory system. They have an incomplete digestive system and therefore use the same orifice for intake of food and expulsion of waste materials.
  
  So basically, they poop out of their mouths. Ewwww...
  
  
• Jellyfish go through several stages during their lifecycle and the form that you usually associate with jellyfish, medusas, is only one of them. There is for instance a phase called planula, where the jellyfish is in a type of larval stage. The planulae eventually attach themselves to surfaces where they become polyps which later turn into to medusas.
  
  
• Jellyfish swim by contracting and expanding their bodies. They do not have scales or shells. If exposed to the hot sun, they disappear, leaving only a circle of film. Jellyfish have a defense mechanism of oral arms or tentacles which are covered with organelles called nematocysts. These nematocysts are paired with a capsule which contains a coiled filament that stings. The filament unwinds and launches into the target, thereby injecting toxins upon contact by foreign bodies.
  

Stay tuned to Ugly Fish for more fascinating facts about Jellyfish!