Just how smart is an octopus?
Total anecdote here, but when I volunteered at our aquarium in Charleston, SC (amazing aquarium, go check it out), we had a problem where our flounder were vanishing from their tank. We suspected theft and so put a camera up in the back room. The next time flounder disappeared we checked the feed - one of our octopi was escaping from his tank that we thought we had already anti-octopus'd, climbing over the walls, breaking into the flounder tank, eating a flounder, and then breaking back out of the flounder tank and back into his.The weird thing isn't that he went to go eat a flounder, it's that he broke back into his own tank after, leaving us scratching our head for weeks over where the flounder were going. Obviously if we came in one day to see an octopus in the flounder tank the mystery would be solved day 1.Anyway we put carpet on the walls so his little suckers couldn't stick and let him carouse around the aquarium like some sort of aquatic monkey.