12 Terrifying Facts About Jellyfish.Second fact

Second factor

Jellyfish are invertebrates but some, such as box jellyfish, can hunt medium-sized fish and crustaceans. The ox jellyfish does have some unique features that set it apart from other jellyfish: it has eyes with retinas, corneas, and lenses and a brain that can learn, remember and direct complex behaviors (like swimming 21 feet per minute.)

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