Invertebrates
Mimic Octopus
Thaumoctopus mimicus · also called mimic octopuses
A mimic octopus crosses open sand with almost no cover in sight, and within seconds solves the problem by becoming something else entirely: flattening into the outline of a poisonous sole, or trailing two arms behind it banded like a sea snake, or spreading the rest into something close to a lionfish’s venomous fan of spines. It has no shell, no reef, and no real hiding place, so it borrows someone else’s reputation instead.
Overview
The mimic octopus, Thaumoctopus mimicus, is a shallow-water octopus native to sandy and muddy seafloor habitat in the tropical Indo-Pacific. Lacking the shelter most octopuses rely on, it defends itself by reshaping its soft body into convincing impressions of other, more dangerous animals.
Picking the right threat to borrow
What sets the mimic octopus apart from ordinary camouflage is apparent selectivity: researchers have observed it favouring specific disguises, such as a banded sea snake impression, that most closely match whatever predator happens to be nearby at the time.
Status
Data Deficient — only formally described in the early 2000s, with population data across its Indo-Pacific range still limited.
Mimic Octopus: common questions
How many different animals can a mimic octopus imitate?
A mimic octopus has been observed reshaping its body, colour, and movement to resemble several different animals, most notably a flattened sole, a banded sea snake, and a lionfish with spread fins, and researchers suspect the full range of impressions it is capable of producing may be broader still, given the flexibility of its soft, boneless body.
Does a mimic octopus choose which disguise to use?
Researchers have observed apparent evidence that a mimic octopus selects a specific disguise based on the type of predator threatening it at the time, such as adopting a banded sea snake impression when faced with a predator that specifically avoids sea snakes, suggesting a genuinely situational rather than random approach to its mimicry.
Why does the mimic octopus live on open sand instead of a reef?
The mimic octopus is typically found on open sandy or muddy seafloor with little natural shelter, a habitat where its unusual defensive strategy of active mimicry plays an especially important role, since the animal cannot rely on rocky crevices or coral cover the way many other reef-dwelling octopus species do.
When was the mimic octopus first described by scientists?
The mimic octopus was not formally described in the scientific literature until the early 2000s, making it a comparatively recent discovery despite how visually striking and easily observable its mimicry behaviour is once a diver or researcher encounters the species performing it in the wild.