Pissed off Octopus Destroys Aquarium

Otto the octopus wreaks havoc

A octopus has caused havoc in his aquarium by performing juggling tricks using his fellow occupants, smashing rocks against the glass and turning off the power by shortcircuiting a lamp.
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Staff believe that the octopus called Otto had been annoyed by the bright light shining into his aquarium and had discovered he could extinguish it by climbing onto the rim of his tank and squirting a jet of water in its direction.
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"Once we saw him juggling the hermit crabs in his tank, another time he threw stones against the glass damaging it. And from time to time he completely re-arranges his tank to make it suit his own taste better - much to the distress of his fellow tank inhabitants."

Octopi are disturbingly intelligent. They can open screw caps on jars, be trained like dogs and allegedly learn by simple observation. Some are able to change colors and movement patterns to mimic several different species, and apparently a few have even broken into the holds of fishing boats to eat their catch. Cephalopod intelligence isn't limited to octopi, either - some kinds of squid exhibit complex communication through color changes.