Today is World Jellyfish Day! Here are five cool facts about jellyfish:
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Jellyfish are among the oldest living creatures on Earth, dating back over 500 million years. They have existed longer than dinosaurs, sharks, and even trees.
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Jellyfish do not have a brain, heart, or bones. Instead, they possess a simple nerve net that allows them to respond to their environment, swim, and capture prey.
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Some jellyfish species can produce light through a process known as bioluminescence. This ability can help them evade predators, attract prey, or communicate with other jellyfish.
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There are over 2,000 known species of jellyfish, ranging in size from a few millimetres to over 2 meters in diameter. Some species include the moon jelly, lion's mane jellyfish, and the immortal jellyfish, which can revert to its juvenile form and potentially escape death.
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Jellyfish use specialised cells called nematocysts to capture prey and defend themselves. These cells can inject venom, which varies in potency from mild to deadly, depending on the jellyfish species. Some, like the box jellyfish, have stings that can be extremely painful or even lethal to humans.
Jellyfish are fascinating creatures that continue to intrigue scientists and everyone.
