I have never heard of an animal mimic mimicking yet another animal mimic, but that’s what a new paper in Coral Reefs (reference and free link below) describes.
I’ve written before about the mimic octopus (Thaumoctopus mimicus), which has extraordinary abilities to alter both its color and its shape (see video at link above) to mimic not only its background, but also other species like lionfish, sea snakes, and soles, all of which are poisonous and all of which have an “aposematic” (warning) pattern of stripes.
Predators have hence learned to avoid this pattern, which then forms the basis for the evolution of “Batesian mimicry” by the octopus. (In that form of mimicry, a palatable animal evolves a pattern resembling that of a distasteful or dangerous species so as to gain protection from predators who have learned to associate the aposematic pattern with foulness and so avoid it. The black-and-orange striped pattern of “hornet moths” is an example.). As a potential predator of hornets (many of you have swatted them, I bet), you would certainly shy away from this harmless moth, a Batesian mimic:
Now, however, we have a new form of mimicry in which a palatable species imitates and associates with another palatable species. Here’s from the short, one-page paper:
The Mimic Octopus (Thaumoctopus mimicus) is a remarkable imitator, apparently assuming shape and behaviour similar to models as diverse as poisonous Lionfish, Soles and Sea Snakes (Norman et al. 2001). All of those models share in common stripped brown and beige or black and white colour patterns. During a diving trip to the Lembeh Strait (North Sulawesi, Indonesia) in July of 2011, the third author filmed a Mimic Octopus for about 15 min and recorded an unexpected relationship: the Black-Marble Jawfish (Stalix cf. histrio) followed the Mimic Octopus for several minutes, remaining very close to the octopus’ arms. . . The colour of the Jawfish matched the banded pattern and colour tone of the octopus.
The jawfish is apparently a weak swimmer, and uses the octopus as a cover, apparently to move around more freely. In some areas, though, the jawfish occurs without the octopus, so the authors regard this as a case of “opportunistic mimicry”. It would be interesting to see (this isn’t mentioned in the article) whether the jawfish’s pattern has changed in areas where its range overlaps the octopus, which would indicate that some of that mimicry is based on evolutionary change in the fish rather than its just learning (or evolving) to behave in such a way that takes advantage of its pre-evolved pattern.
At any rate, here’s the video of the behavior. The jawfish (initially highlighted in the circle) is remarkably camouflaged.
And here’s the Black-Marble jawfish:
h/t: Matthew Cobb
Rocha, L. A., R. Ross, and G. Kopp. 2012. Opportunistic mimicry by a jawfish. Coral Reefs. Online: DOI: 10.1007/s00338-011-0855-y (free at the link).