The infamous box jellyfish developed its frighteningly powerful venom to instantly stun or kill prey, like fish and shrimp, so their struggle to escape wouldn’t damage its delicate tentacles.
Their venom is considered to be among the most deadly in the world, containing toxins that attack the heart, nervous system, and skin cells. It is so overpoweringly painful, human victims have been known to go into shock and drown or die of heart failure before even reaching shore. Survivors can experience considerable pain for weeks and often have significant scarring where the tentacles made contact.
Average life span in the wild: Less than 1 year
Size: 10 ft (3 m) long; 10 in (25 cm) across
Weight: Up to 4.4 lbs (2 kg)
Group name: Fluther or smack
Did you know? Sea turtles are unaffected by the sting of the box jellyfish and regularly eat them.
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