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Sea urchins



Category: Invertebrates



These small, spiny, globular animals inhabit all the oceans of the world and can survive in shallow intertidal zones, 5000 meter deep abyssal zones, and nearly anything in between. They move slowly about on their hydraulic tube feet, feeding mostly on algae. Sea urchins are able to adjust their metabolisms to the level of nutrition available in their environment. Many species of animals, including humans, hunt and eat sea urchins. Their internal organs are protected by a hard shell called a “test”, to which their spines are attached via rounded turbercles. The spines serve as protection and are toxic in some species.



Data & Facts

Scientific Classification
Kingdom - Animalia
Phylum - Echinodermata
Class - Echinoidea

Did you know?
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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