Jellyfish are enigmatic and fascinating creatures that have existed for more than 500 million years. They are found in oceans worldwide and come in various colors, shapes, and sizes. Though these creatures have a simple body structure, they have various unique characteristics.
Jellyfish or sea jellies are the medusa-phase of specific gelatinous creatures of the subphylum Medusozoa, a major part of the phylum Cnidaria. These are free-swimming marine animals that have umbrella-shaped bells and also trailing tentacles.
However, some are anchored to the sea beds instead of being mobile. So, in this article, we will explore some really amazing facts about this amazing sea creature called Jellyfish.
Facts About Jellyfish:
They have stinging cells:
Jellyfish have numerous stinging cells located on their long tentacles. Those stinging cells are full of venom. Jellyfish use these cells to protect themselves from predators or attackers.
When these tentacles are triggered or touched, the stinging cells immediately release venom that can penetrate the attacker’s skin. Jellyfish also use their venom to catch their victims.
They are not fish:
Despite being called jellyfish, these unique creatures are not fish. In fact, they are invertebrates, which means they don’t have a backbone. Instead, they belong to Cnidaria, which includes creatures like coral, sea anemones, and hydras.
Moreover, jellyfish usually eat various types of food. They eat various types of marine creatures, such as shrimps, small fish, larvae, eat crabs, and even tiny plants. They can even eat other jellyfish.
There are more than 2000 species:
There are more than 2000 species of jellyfish. Those species range from the tiny Irukandji jellyfish, just the size of a fingernail, to the huge lion’s mane jellyfish, which have tentacles over 100 feet long.
Another amazing species of jellyfish is the Crystal jellyfish. It is one of the largest types of jellyfish seen in the western part of North America. These creatures have around 150 long tentacles and stings but are not dangerous to humans. They can swallow another jellyfish of half their size by expanding their mouth.
They have been around for more than 500 million years:
Jellyfish are one of the oldest creatures present on Earth. Fossil evidence shows that jellyfish have existed for over 500 million years, making them older than dinosaurs.
Also, they are incredibly lightweight creatures because their bodies comprise over 95% water. This enables them to float in the ocean without any effort.
They have no organs, bones, muscles, or even a brain or central nervous system:
Jellyfish do not have any bones, organs, or even muscles. Instead, they depend on a system of water-filled canals to move around and perform several basic functions.
In addition to this, jellyfish don’t have a brain or even a central nervous system. Instead, they have a simple nervous system that lets them sense their surroundings and respond to stimuli.
Some of them can be highly poisonous:
A specific jellyfish species, the Box jellyfish, is highly poisonous. These jellyfish are named like this due to their cube-like shape. They have tentacles covered by poison, which may be fatal because it could cause cardiac arrest in human beings.
Box jellyfish can be seen in the Indo-Pacific Ocean and the northern Australian coasts. These jellyfish can swim really fast, like 1.5 to 2 meters per second.
Some of them are bioluminescent:
Some species of jellyfish are bioluminescent, meaning they can produce light. This can be regarded as a defense mechanism, as their bright light can startle predators and give the jellyfish a chance to escape.
In contrast, they even use this light to lure their prey. The bright light sometimes makes them look like small sea animals and can easily attract and lure their prey.
Some jellyfish have a symbiotic relationship with others:
Some species of jellyfish have a symbiotic relationship with various other animals. For example, certain types of crabs and shrimp. These animals will attach themselves to the jellyfish and use it as protection from predators. On the other hand, the jellyfish benefits from the small animals feeding on its parasites.
Jellyfish bloom can bring devastating effects on marine ecosystems:
Jellyfish blooms, which happens when there is a sudden increase in the population of jellyfish. This may have devastating effects on marine ecosystems. They can damage fishing equipment, clog fishing nets, and even disrupt power plants by blocking water intake pipes. Moreover, jellyfish even sting thousands of swimmers every year.
Moreover, they can even shut down nuclear plants, as nuclear power plants use ocean water. Jellyfish can clog the cooling intakes of the nuclear plant. When the cooling water stops flowing, turbines will not be able to work, resulting in power reductions or shutdowns of those plants.
Some of them are immortal creatures:
Turritopsisdohrnii is known as immortal jellyfish because they start as a larva and turn into fertilized eggs. This species of jellyfish matures in a few weeks and is almost 4.5 millimeters wide.
This species of jellyfish not only live for many years, but they also have eternal life. In response to physical damage or maturity, they can go back to their stage of development or start again as a polyp, which is when they remain attached to coral reefs.
Jellyfish have just one part for pooping and eating:
Jellyfish use their tentacles to catch prey and transport food to their mouths. Their mouths are in the center of their bell-like body, with a small opening.
They use their mouths to both eat food and release waste. Sometimes, they even squirt to propel themselves in the water.
Jellyfish can reproduce both sexually and asexually:
The adult stage of jellyfish is called Medusa. This medusa can reproduce sexually by spawning sperm cells and eggs deposited into the water. Male and female jellies release their sperm cells and eggs through their mouths. The fertilization of eggs happens in the water. However, in some other species, sperms enter the female jellyfish’s mouth and are fertilized within the body.
After fertilization, jellyfish go through the polyp stage. In this stage, they look like sea anemones and hold to a smooth surface or rock. In this stage, jellyfish can reproduce asexually by a cloning procedure. The cloned jellyfish is known as ephyra.
Their lifespan varies:
The lifespan of a sea jelly depends on various factors. First is their species or type. Some of them have a lifespan of 12 to 18 years. In contrast, others live only for around three months to a year, and some have a lifespan of three to six months.
Some other factors, like weather, water temperature, and predators, can also affect the lifespan of a specific species of jellyfish.
Some jellyfish have several eyes, but some are without eyes:
Box jellyfish have 24 eyes. Their eyes are grouped into four parts at each corner of their bell-shaped bodies. Two eye types can create images, while the other groups can perform simpler tasks, such as avoiding obstacles and responding to light.
However, most jellyfish have a simple body structure, so they don’t have any eyes. However, these creatures can still detect light and sense their environment through the particular nerve net attached to the end of their tentacles. This nerve net usually spreads apart on their tentacles.
Jellyfish are highly nutritious:
Some species of jellyfish are safe food. Moreover, each type of this creature contains different amounts of nutritional content. According to research, jellyfish are a good source of protein antioxidants and several important minerals.
A cup of edible, dried jellyfish has; 3 grams of protein, 1 gram of fat, 7% of iron, and several other nutrients, such as phosphorus, calcium, and magnesium.
They can adjust to the changes in the environment:
As per research, this amazing creature can adjust according to environmental changes, such as water pollution, climate change, and warming seas. Moreover, unlike other sea creatures, they can adapt to low oxygen levels.
Also, the construction structures in water, like artificial reefs, oil platforms, piers, etc., can be a good habitat for jellyfish.
Another interesting fact is that jellyfish can release their sting faster than a bullet or a sports car. They need 700 nanoseconds to shoot their stings and hit a target.
NASA sent more than 2000 polyps to space
NASA sent more than 2000 anemone-like jellyfish or polyps to outer space. This experiment is conducted to study how the lack of gravity can affect the development procedure of a jellyfish.
Those creatures are kept in bags and flasks with artificial seawater. Also, they are injected with chemicals that will encourage them to reproduce.
They have inspired many artists:
The fascinating beauty of jellyfish has inspired designers and artists for centuries. Some artists have even used real jellyfish in their works of art, while others have created installations and sculptures inspired by their unique movements and shapes.
They have even inspired advances in technology. For instance, humans have developed a jellyfish-inspired robot that could be used for underwater surveillance and exploration.
Hence, these sea creatures, known as jellyfish, play a vital role in marine ecosystems and inspire science, technology, and art advances. At the end of this article, we learned about 18 amazing facts about this fascinating sea creature. These facts offer us a clear picture of this fascinating creature of our ecosystem. To know more, you can see our website.
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