Few animals can blow our minds like octopuses. They are extremely smart, they regularly eat one another, and they're the animal kingdom’s most impressive escape artists. This last fact was first proven in 2008 when scientists at the University of Melbourne spotted the southern sand octopus burrowing away during a night dive in Port Philip Bay, Australia. After the researchers shined a light on the octopus, it began to shoot jets of water into the sand below, creating a pit of quicksand. Research on this response—the first time a cephalopod has been seen forming a complete burrow—has just been published in the journal Behaviour.
Jasper Montana, of the University of Melbourne, told New Scientist, "It actually was a pocket—like a space that the octopus could sit within. So it was a true burrow." The process of creating this burrow required the octopus to use its arms to create a "chimney" to breathe through. It then solidified the walls of the chamber with a layer of mucus.
Unlike a lot of octopus species, the southern sand octopus lacks the ability to camouflage itself. So this subterranean burrowing is believed to be this creature's method of self-protection from predators.
Katherine Harmon Courage, author of Octopus! The Most Mysterious Creature In the Sea, told the Huffington Post, "This is another amazing example of how octopuses continue to surprise us with their intelligence—and ingenuity. To find an octopus that builds a custom subterranean den in the sand (even if it's made partially out of mucus!) is very cool."