An alarming video shared by lifeguards shows just how easily the venomous Irukandji jellyfish can go unseen when swimming in ...

A British tourist has died after being stung by a tiny, nearly-invisible jellyfish while swimming off Hamilton Island in tropical northern Australia, authorities said today. The British High ...

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.

The ocean is a beautiful, mysterious world full of incredible creatures—but not all of them are as harmless as they seem. Beneath the waves lurk animals that can switch from serene to sinister in the ...

Even the tiniest encounter can cause severe symptoms and possible death, despite being barely visible in the ocean.