10 Fun Facts About Jellyfish

Jellyfish, the wobbly wonders of the ocean, often astound with their unique shapes, sizes, and stings. Learn more about these marine marvels as we dive deeper into the underwater world.

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[Polyautistic]

This video presents 10 fun facts about jellyfish, such as their anatomy, behavior, reproduction, and history. It also explains why jellyfish are not fish, and why some of them are immortal and dangerous. It also introduces some of the most amazing and dangerous jellyfish species in the world.

Highlights:

[00:00:00]
The jellyfish’s ancient history

Existed for more than 500 million years
Lived before the first dinosaurs

[00:00:18]
The jellyfish’s simple body structure

No brains, hearts, bones, or lungs
Have a nervous system with 10, 000 neurons
Can sense light and other changes in the water

[00:00:33]
The jellyfish’s ability to glow in the dark

Approximately half of all jellyfish are bioluminescent
Use light to deter predators and attract prey

[00:00:44]
The jellyfish’s classification and diversity

Not actually fish, but a type of plankton
Related to sea anemones and corals
The lion’s mane jellyfish is the largest known jellyfish species
It can have a diameter of over 7 feet and tentacles of over 120 feet
The Irukandji jellyfish is the smallest and one of the most venomous jellyfish species
It is only about 1 cm in size

[00:01:15]
The jellyfish’s space adventure

NASA sent thousands of jellyfish into orbit to test the effects of gravity
The jellies born in space struggled to move normally on Earth

[00:01:27]
The jellyfish’s reproductive cycle

A single jellyfish can reproduce all by itself
Adults release sperm and eggs into the water, which grow into polyps
The polyps can then asexually clone themselves by budding

[00:01:40]
The jellyfish’s immortality trick

The turritopsis dohrnii or the immortal jellyfish can turn back time
It reverts into a polyp when facing danger
The polyp can then create a new adult jellyfish

[00:02:01]
The jellyfish’s venomous sting

The box jellyfish is the most venomous jellyfish in the world
It has eyes and hunts for small fish and shrimp
Its sting can cause cardiac arrest or death in humans within minutes

[00:02:21]
The jellyfish’s post-mortem threat

Dead jellyfish can still sting and release venom
Their tentacles remain active after death

[00:02:29]
The jellyfish’s playful names

Some jellyfish have colorful and funny names
Examples are flower hat, pink meanie, blue blubber, and purple people eater

[sudharaghu]

Thank you for the facts it helped me a lot