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Category: Invertebrates



Jellyfish are typically free-swimming animals consisting of a gelatinous, inverted-umbrella body form (the bell) with trailing tentacles. Having roamed the sea for the last 500 (and maybe 700!) million years, they are the oldest known multi-cellular animal. Since jellyfish are not true fish, many experts prefer to use the name “jellies” to avoid cultivating misconceptions. The body of a jellyfish is between 95% and 98% water and most do not have specialized digestive, osmoregulatory, central nervous, respiratory, or circulatory systems. They can range in size from about 1 millimeter to a bell height and diameter of over 2 meters (6.6 feet). The lion’s mane jellyfish (Cyanea capillata) has fine, threadlike tentacles that may extend over 36.5 meters (120 feet!).



Data & Facts

Scientific Classification
Kingdom - Animalia
Phylum - Cnidaria

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Interesting Animal Facts

Body horror in the insect kingdom

Learning about animals, you can discover many fascinating, even beautiful facts, but there are also things that can give you nightmares! Enter the strepsiptera (“twisted-wing parasite”). The adult female has no limbs, wings, or mouth - she simply lives in and feeds off her host (typically a wasp). When it becomes time to mate, she protrudes part of her abdomen from between the plates of her host and uses mind control to get the wasp to fly off to nearby males. Sexually mature males have wings, and fly around for about five hours before dying - spending their entire short existence seeking out females to mate with. After the female is impregnated, her own young grow and consume her. And once there is nothing left to eat, they leave their host wasp, infiltrate the nursery, and latch on to a larvae to create their own “zombie wasp” host and continue the grisly cycle!

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