The marine life is quite diverse, with various species being discovered regularly. Did you know that we haven’t explored more than 80% of the oceans and we don’t always know what happens down there?
The little we know about life in the oceans has given us slight knowledge of how marine life works. Jellyfish are part of this exotic marine life. There is more to these sea creatures than meets the eye.
There are approximately 2000 species of jellyfish known to man, although there is a probability there could be more than 300000. The species will vary based on size, color, and body build. Here are some details that can help you understand jellyfish better.
The life cycle of a jellyfish is quite sophisticated since reproduction takes place both sexually and asexually. The reproduction stage of a jellyfish is known as medusa. Adults release eggs and sperms which are released into the water. The eggs are fertilized and develop into larvae planula.
The larva will swim in search of a place to settle. Once the larvae planula finds a suitable site, it will settle there where it develops to a polyp. The polyp does not have any motor functions and will float freely in the water or dwell at the sea bottom or attached to little vegetation. The polyps are usually millimeters in size.
Maturity and Reproduction
The polyp then reproduces asexually through cell division, a process called budding. The polyp then develops tentacles that are reabsorbed into the body as the body starts narrowing down. The polyp then develops into a medusa, which is identified as an adult jellyfish.
There is little knowledge about how long jellyfish can live. Some species have recorded to be immortal due to their ability to transform from medusa back to the polyp. This reversal helps the medusa to avoid threats that would lead make the jellyfish prey.
Jellyfish have been proven to be among the most efficient swimmers in the animal kingdom. They move through the expansion and contraction of muscles on their umbrella-shaped bodies, thus pushing water behind. This mechanism enables them to move efficiently through water without consuming a lot of food or oxygen. Their body contractions and expansion enables them to save on energy spent in movement.
Jellyfish are generally predatory or parasitic. Amazingly, the biggest threat to jellyfish is other jellyfish. Most of the time, jellyfish feed on small fish, fish eggs, larvae, or crustaceans. Their swimming technique also helps them to hunt their prey since the umbrella-like bodies will expand to suck in water. This movement enables them to reach the victim with their tentacles easily.
Hunting and symbiosis
The tentacles contain a neurotoxin that helps them to paralyze or kill their prey. There are a few other species of jellyfish that feed on planktons.
Most jellyfish species have a symbiotic relationship with other forms of marine life. There are some small fish that are not susceptible to jellyfish stings and may live among the tentacles. They act as bait that helps the jellyfish get its next meal.
Most jellyfish inhabit the sea. There are very few species that live in freshwater. You will find most jellyfish at the bottom of the sea or shallow lagoons.
Fun Facts about Jellyfish
Yet, there are more surprising facts that make these sea creatures more fascinating. Here are a few additional details that you’ll find remarkable about jellyfish.
- Jellyfish aren’t a type of fish. They don’t have a backbone structure and are made up of specialized membranes, which helps them absorb oxygen from the water. Their anatomy consists of mostly water and tissues.
- Jellyfish have no brain. Jellyfish neither have a respiratory system as they absorb oxygen through special membranes. Their bodies are approximately 95% water.
- A group of jellyfish is known as a smack.
- A jellyfish can regenerate lost parts.
- Jellyfish are considered immortal. This fact is because they are known to morph backward and return to their polyp stage.
- Some jellyfish are eaten and are a delicacy in some countries.
- Collagen can be harvested from jellyfish and used for several medical purposes such as treatment of arthritis.
- Most jellyfish stings are not fatal. However, stings from some box jellyfish can be fatal. The stings can lead to severe allergic reactions that lead to lethal shock.
- A jellyfish is called medusa. It’s the name of a goddess in Greek mythology.
- A jellyfish’s mouth also functions as an anus.
Jellyfish has thousands of species, which may range based on anatomy, size, and habitat. A good number of jellyfish are, therefore, not endangered. In some countries, jellyfish are harvested for food. Additionally, they are utilized to obtain collagen, a protein used for various medical applications.