The evolution of conspicuous facultative mimicry in octopuses: an example of secondary adaptation?

Working with the California Academy of Sciences which publicized her work, CI-Indonesia’s Crissy Huffard has been studying the evolution of mimicry in Indonesian octopus, which can which can impersonate flatfish, lionfish, and sea snakes to dupe potential predators. 

Her work was recently published in the Biological Journal of the Linnean Society.

(photo left) The ‘Mimic Octopus’ Thaumoctopus mimicus changes its pattern and behavior to imitate a flatfish – an unusually conspicuous primary defense mechanism.

IN DEPTH: Read a blog from Dr. Crissy Huffard about this discovery and her work in Indonesia.


Abstract:
The 'Mimic Octopus' Thaumoctopus mimicus Norman & Hochberg, 2005 exhibits a conspicuous primary defence mechanism (high-contrast colour pattern during ‘flatfish swimming’) that may involve facultative imperfect mimicry of conspicuous and/or inconspicuous models, both toxic and non-toxic (Soleidae and Bothidae). Here, we examine relationships between behavioural and morphological elements of conspicuous flatfish swimming in extant octopodids (Cephalopoda: Octopodidae), and reconstructed ancestral states, to examine potential influences on the evolution of this rare defence mechanism. We address the order of trait distribution to explore whether conspicuous flatfish swimming may be an exaptation that usurps a previously evolved form of locomotion for a new purpose. Contrary to our predictions, based on the relationships we examined, flatfish swimming appears to have evolved concurrently with extremely long arms, in a clade of sand-dwelling species. The conspicuous body colour pattern displayed by swimming T. mimicus may represent a secondary adaptation potentially allowing for mimicry of a toxic sole, improved disruptive coloration, and/or aposematic coloration.

These findings were published in Huffard CL, Saarman N, Hamilton H, and Simison WB. 2010. The evolution of conspicuous facultative mimicry in octopus: an example of secondary adaptation? Biological Journal of the Linnean Society 101: 68-77
Available online: http://onlinelibrary.wiley.com/doi/10.1111/j.1095-8312.2007.00948.x/abstract

Indonesia     Octopus; Species; Mimicry