One of the most charismatic creatures of the ocean, octopuses are perhaps best known for their incredible camouflaging abilities. Along with other members of class Cephalopoda – namely squid and cuttlefish – octopuses have a uniquely fine-scale control over their coloration and skin texture, and they are capable of completely shifting their appearance in fractions of a second.

The iridophores use reflecting plates instead of pigment sacs, which allows them to create the iridescent golds, greens, blues, and silvers visible on cephalopods. The leucophores mirror the ambient color of the environment, which helps the cephalopod to blend in even more. As if such versatile coloration wasn’t enough, cephalopod skin also has dense fine-scale muscle groups that can create and shape protrusions in the skin called papillae. This allows the animal to mimic the textures of sponges, corals, algaes, rocks, and more.

All of this together makes cephalopods masters of camouflage, hiding away from both predators and prey. Cephalopods, especially cuttlefish and squid, will also use their control over their appearance to communicate, often creating visually stunning courtship or aggression patterns. But there is one species that has taken this camouflage ability to the next level: the mimic octopus.

For example, when a mimic octopus is in danger of attacks from the notoriously territorial damselfish, it will use two arms to mimic the banded sea snake, a poisonous predator of damselfish. To do this, the octopus will stick itself into a hole, leaving just two arms out. It then lines these two arms up so that they appear to form one continuous “snake,” complete with the snake’s signature black and grey banded coloration. The octopus is able to mimic the movements of the snake as well by waving its arms in an undulating motion. It even includes the shape and motion of a head in its mimicry. Details like this make sure the damselfish stay away, scared of encountering what they assume to be one of their predators.

While a banded sea snake mimicry can protect the octopus in sheltered areas, the mimic is exposed to predators when it crosses expanses of the sandy bottom between foraging spots. To stay safe, the octopus often travels under the guise of a common flatfish. To do this, the octopus rearranges itself into the streamlined, flattened oval shape and coloration of a poisonous and well-camouflaged sole species found in that area. It trails its arms behind itself and adopts the flatfish’s quick undulating movement, close to the seafloor. Safely disguised as a dangerous species, the octopus is free to travel to its next foraging site.

The octopus has also been observed mimicing the lionfish, another dangerous fish. Covered in long banner-like spines tipped with venom, the lionfish is avoided by most predators. By swimming higher in the water column and spreading out arms striped with the reds, oranges, and whites of the lionfish’s spines, the mimic is able to safely travel through the water column as well. 

These are just three examples of species the mimic octopus has been observed impersonating. Such mastery of detail, motor control, observation, and decision-making are a testament to the intelligence of cephalopods like the mimic octopus. There is still a long way to go before we fully understand the behavior and intelligence of the mimic octopus, as very little research has been done on it. The research that has been published has only sparked more questions about cephalopod self-awareness, consciousness, body image, and intentional versus instinctual deception and camouflage. As research efforts continue, we can only imagine what else we will learn about this fascinating and unique creature.

Cover Image: Mimic octopus (Thaumoctopus mimicus). Wikimedia (photo by Elias Levy).