Octopus Ink: What Does it Do?

A few years back, we explored the the mechanics of how octopus inking works. To recap, octopuses have an ink sac located near their digestive system, and when necessary, they can eject ink out of the sac accompanied by a burst of water to serve as a smokescreen to confuse predators while the octopus swims away.

Octopuses have two main methods of inking. The first type is the one with which we are most familiar. The octopus will squirt a large cloud of ink, then make a quick getaway, leaving behind a predator befuddled by the inky smokescreen. Sometimes though, the octopus will release several small clouds of ink approximately the same size as the octopus itself meant to be pseudomorphs or "false bodies" that serve as decoys to confuse the predator. What's interesting is that the composition of these smaller ink "bodies" differs from that of one large ink cloud as they contain greater amounts of mucus, thereby allowing them to hold their form longer while the octopus - or cephalopod - escapes.

This method, commonly referred to as "blanch-ink-jet maneuver", is so effective a variety of species have been witnessed attacking the false bodies.

Wait - it gets better! There is some evidence to suggest that certain chemical compounds found in octopus ink actually suppress or disable certain predators' chemosensory systems, leading scientists to believe that octopus ink is much more than a mere smokescreen.

Cephalopod ink has been shown to contain several chemicals with some varieties depending on the species. The primary components are melanin and mucus. Tyrosinase, dopamine and L-DOPA, and small amounts of amino acids, including taurine, aspartic acid, glutamic acid, alanine and lysine are also known constituents of octopus ink.

While there is still much research to be done, recent evidence suggests that cephalopod ink is toxic to tumor cells.

We have a long way to go to uncover the many mysteries shrouding the octopus, so please join us as we continue to explore and celebrate everything octopus.