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    Introducing The Flamboyant Cuttlefish
    By Danna Staaf | October 28th 2009 10:29 AM | 4 comments | Print | E-mail | Track Comments
    About Danna

    Cephalopods have been rocking my world since I was in grade school. I pursued them through a BA in marine biology at the University of California...

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    Speaking of cephalopods which have surprised by not being too heavy to fly after all, I was reminded of one little cuttlefish who is actually too heavy to swim: Metasepia pfefferi, or Pfeffer's Flamboyant Cuttlefish. With the scientist's charming penchant for repurposing ordinary adjectives, biologists describe the body of this little fellow as "robust," which means that it is chubby in all dimensions. It may sound insulting to keep calling it heavy and chubby, but actually these features make for a very cool trick.

    The Flamboyant doesn't swim and hover midwater like other cuttlefish. Instead, it crawls on the seafloor like an octopus.

    This behavior is related to its reduced cuttlebone. A cuttlebone is the "skeleton" of a cuttlefish, intermediate between the robust shell of a nautilus and the slender pen of a squid. It's internal like the pen, but calcified and chambered like the nautilus shell. These chambers are full of gas and liquid, the relative concentrations of which the animal can alter in order to change its buoyancy.

    Because of its extra-small cuttlebone, the Flamboyant has a hard time with buoyancy. It can't swim for very long without sinking to the bottom. But what it lacks in buoyancy, it makes up in flambuoyancy!


    I want to be an octopus, I want it so bad.

    Not only does it crawl around the bottom like an octopus, it's the only one of the only non-octopus cephalopods found to be toxic. The bright colors and distinctive posture are probably a warning display, speaking a language that seems to be universal across the animal kingdom: Stand back, I'm toxic, don't eat me!

    Here is a truly rad video with some fun facts about the Flamboyant. The only correction I would offer is that the bite of this cuttlefish isn't known to be venomous. Rather, toxin is found in its muscle tissue, making it more like a pufferfish than a blue-ringed octopus: poisonous, not venomous.

    Comments

    Apparently this guy and the blue-ring aren't the only toxic cephalopods. Pretty much all cepohalopods are venomous though only a few appear to be potent enough to harm a human (flamboyant cuttlefish, blue-ring octopus, and the striped pyjama squid). Here's a pdf of a paper on cephalopod venom, it's pretty cool http://www.venomdoc.com/downloads/2009_Fry_Tentacles_of_Venom.pdf it's not easy reading so here's a news story about it too http://www.abc.net.au/science/articles/2009/04/15/2543328.htm?site=scien...

    Danna Staaf
    Hi Noadi! Sorry for the delay--I posted a long reply yesterday, but apparently it got eaten by my computer or the website or something. On the bright side, it will probably be more coherent as a result of rewriting from memory this morning. =)

    I'm glad you brought up the Fry paper. We had a really interesting discussion in my lab when that came out. In their Introduction, the authors assert that blue-ring tetrodotoxin is fabricated in-house by endosymbiotic Vibrio bacteria. While that could be true, no one in my lab, including a post-doc who's studied TTX for years, has ever seen evidence for it. And the paper itself doesn't cite any references for that claim. That grievance cast a bit of a pall over the rest of the paper, though it is an interesting study. I was also somewhat irked by:
    Several cephalopod species have been confirmed to use envenomation as a mechanism to neutralize captured prey and/or as a defense against predators (Norman and Reid 2000).
    Norman and Reid 2000 is a popular field guide to the cephalopods of Australia. I have tremendous respect for Mark Norman as a scientist, I love this book, and my copy of it is well-worn, but it isn't peer-reviewed literature. It would be more appropriate for them to cite the actual research papers that described envenomation in the first place.

    And, incidentally, in their introductions to each cephalopod sub-taxon, Norman and Reid only mention envenomation in octopuses. Since I've had this book for a long time, it may be one of the reasons I had it in my head that octopuses were the only toxic cephalopods. Which is, in fact, wrong!

    But the counterexamples do not come from Fry's paper, because they didn't find any toxins. They found DNA that codes for proteins that are similar to other proteins that are known to be toxic in other animals. They are well aware of this limitation. Their concluding sentence:
    Further work into the bioactivity of these proteins will be illuminating with regard to their functional diversity and role in predation.
    That means their study didn't address bioactivity--toxicity--of the proteins. They couldn't, because they didn't look at the proteins, just the DNA. I expect at least some will turn out to be toxic; we just don't know yet.

    By comparison, in 2008 this Japanese research group studied toxicity of proteins from the salivary glands of six non-octopus cephalopods: three cuttlefish and three squid. All were toxic againt crabs, some were toxic against mice. Spooky!
    Becky Jungbauer
    biologists describe the body of this little fellow as "robust," which means that it is chubby in all dimensions
    I've been feeling very robust lately. I should probably lay off the sugar-free Skinny Cows.
    Awesome video, thanks. Cephalopods in general, but cuttlefish in particular, are just about the most fascinating creatures on Earth. I could watch them for hours.