The Octopus That Slipped Its Lock

In two thousand sixteen, staff at a small aquarium in New Zealand arrived one morning to a genuine mystery. One of their octopuses, an unremarkable looking creature named Inky, had vanished from his tank overnight. No glass had been broken and no alarm had sounded. He had simply gone, as if he had never been there at all.

A search of the building eventually supplied the answer. Under cover of darkness, Inky had prised open the lid of his own tank, then dragged his body across the cold floor to a narrow drainpipe leading to the ocean. He squeezed inside, worked his way through several metres of tight metal piping, and slid out into open water. By sunrise, he was free.

What makes the story remarkable is not just what Inky did, but what it reveals about how an octopus thinks. Octopuses rank among the most intelligent creatures alive, with roughly as many neurons as a dog. Most of those neurons sit not in the head but along the arms, so each arm operates with a degree of independence, almost as though it had a mind of its own.

This intelligence turns up again and again in laboratories worldwide. Octopuses have learned to unscrew jar lids to reach food, solved multi step puzzles to retrieve a piece of crab from a locked box, and even recognised individual researchers by sight, squirting water at the ones they seemed to dislike.

Even so, scientists still cannot fully explain how such intelligence arose. It evolved along an entirely separate branch of life, long before mammals existed, which is why meeting an octopus's mind feels like the closest thing on Earth to meeting an alien one.

Inky himself was never seen again. The aquarium eventually replaced him with another octopus, though this time they made sure the new tank would be considerably harder to escape from.