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
As the Science and Monitoring Advisor for CI-Indonesia’s Marine Program working in the Bird’s Head Seascape, I have the chance to observe thousands of incredibly unique, colorful, and unusual species that are found nowhere else on earth, or that have become rare elsewhere.
The coral reefs, mangroves, and sandy-bottom communities here are simply mind-boggling, and home to the greatest marine biodiversity left in the ocean, offering us a living laboratory for better understanding how marine ecosystems interact. Cephalopods (squid, octopus, cuttlefish and nautilus) are definitely some of the more charismatic animals out there (yes, I am biased), and few places on earth offer the chance to observe them in their natural element – truly undisturbed, untrawled, unfished, and surrounded by predators. Teaching others about their place in the ecosystem is part of what inspires me to work so far from my home in California.
Cephalopods are incredibly important ecologically, sending protein from the smallest crabs and clams in the ocean around the food web to tuna, sharks, and whales. Yet the same defenses that help them avoid predation also work on scientists – they can be a pain in the rump to find and study. We know very little about how their famed abilities to learn, remember, and change their appearance allow them to survive and reproduce in the wild.
But with the expanding reach of scuba and affordable underwater video/photography, we’re piecing things together and getting amazing glimpses into what it means to live a successful octopus life. Every time a cephalopod biologist dives, we have the chance to turn all previous (cephalopod) work into a tailspin. Or we might finally get to understand an odd body part described in the 1800s and not studied since. For a scientist, this is an inescapable draw.
The Mimic octopus is an especially intriguing subject because it moved into a whole new realm of defenses for octopuses. By working with scientists at the California Academy of Sciences who had expertise in evolutionary genetics we learned that the Mimic’s ancestors had great camouflage abilities, and could even mimic flatfish. This alone should have been good enough of a defense to hide from predators – indeed it seems to work fine for its drably-colored living relatives in Indonesia and Hawaii. But somehow through natural selection mimics evolved a defense that relies on predators seeing them instead of not seeing them.
As in any scientific field, exceptions are exciting discoveries. Now that we know this about the mimic, we can try to figure out why being conspicuous helps a mimic octopus survive. Are they venomous themselves? Even though these octopuses don’t mimic any particular flatfish very well, is it good enough to work in the center of biodiversity, where there may be lots of toxic models? Does this color pattern help mimic octopuses identify potential mates?
Because of overfishing, trawling, sedimentation, and land reclamation, the Mimic’s physical and predatory environments have changed in ways we are only beginning to understand. How will these observant and dynamic animals adjust to these changes? The more we can spend time in the water with them, and compare their present-day behaviors to evolutionary history, the better we can hope to understand how these octopuses got here and where they’re going.
In September we will explore an area of the Bird’s Head Seascape and see nearly pristine octopus habitat. Professor Hamid Toha from UNIPA is studying the population genetics of octopuses while Raja Ampat monitoring team member Rudy Dimara will document octopus species and body-pattern diversity. Will this make us reinvent what we know of Mimic octopuses? We’ll keep you posted!
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.1095-8312.2010.01484.x/abstract
UPDATE: Watch a video of the mimic octopus in action!