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    Madame Argonaut
    By Danna Staaf | August 22nd 2011 04:40 PM | 11 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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    Miriam over at Deep-Sea News recently posted a lovely write-up on the argonaut, or paper nautilus. This reminded me that I, too, once felt the delight of finding a live argonaut in a manta tow cod end.

    So I went digging through my grad school archives and found the video I took--on a miniDV tape, which felt so futuristic then and seems so retro now. How times change.

    Anyway, amateur videographer that I am, I somehow managed to splice the least horrible footage together with a voiceover to create a brief film of the awesomeness that is the argonaut.

    And no, they are-go-not squid, but I found her while I was looking for squid, so that counts, right?




    (That's "I Wish You Well" in the background, by Bill Withers, which makes a nice chill soundtrack for sorting plankton all night long.)

    Comments

    Hank
     nice chill soundtrack for sorting plankton all night long.
    Riiiiiight.  You people need much better metaphors for having sex.  Might I suggest something like TV On the Radio's “Wolf Like Me” and When the moon is round and full / gonna bust that box / gotta gut that fish



    It's the best I could do.  I don't know of any actual plankton metaphors, yours was the first.
    Danna Staaf
    Oh dear, I must have been unclear! My sincere apologies. You see, I actually stayed up all night sorting plankton.

    Still, thank you for the video--I feel I will certainly have use for the "Biology prevails!" screenshot.
    Thanks so much for posting this video. I hope to see one of these myself one day.

    Danna Staaf
    I hope you do too! I imagine you might feel a special connection to them, given your namesake. =)
    SO COOL. So very very very cool. Thank you for saving me from my photo/video fail!

    Danna Staaf
    And thank you for the motivation!
    rholley
    What a wonderful creature.  It makes me want to break out in Neapolitan song!

    I immediately consulted our modern day oracle Wikipedia, to wit the article Argonaut (animal).  However, I have come away with more questions than answers (which I think was also a common occurrence with the oracle at Delphi).

    I can understand how the Nautilus shell develops in a logarithmic spiral, since the animal itself is growing bigger, and having increased by so many percent, it lays down another chamber.  Since this percent is in proportion to the size it laid down the previous chamber, one automatically generates a geometric progression.  One can see why mathematicians love that creature.

    In the Argonaut, is there some specialized generating organ, perhaps the egg sac itself, which behaves in the same way?

    Does the Argonaut produce several of these in its lifetime?  Or maybe, does it only reproduce once, like the common octopus?  I understand that said paragon of the maternal instinct starves itself while guarding its eggs, so as not to contaminate them with waste matter.

    In fact, having looked again at the ‘shell’, it doesn’t seem such a close approximation to the logarithmic spiral after all.
    Robert H. Olley / Quondam Physics Department / University of Reading / England
    Danna Staaf
    Nice, very nice nod to the classics! Good questions too. The evolution of the argonaut is still quite mysterious, and the striking similarity between the shape of its shell and the shape of the extinct ammonites is ample fodder for conjecture. One idea is that the argonauts started out living in old ammonite shells (the way intertidal octopuses will sometimes inhabit snail shells) then eventually began to repair them, and finally build them entirely from scratch. In that scenario, the shape of the shell is purely historical--argnoauts make them that way just because ammonites made them that way.

    I believe argonauts are one-time spawners and make only one shell.
    I was fascinated to read on Wikipedia that argonauts were the original beasts to be called "nautiluses", with the chambered nautilus named after them! I guess then when we decided that the two weren't the same kind of thing after all, those upstart chambered guys got to keep the name and the paper nautiluses had to go searching for a new one?

    Danna Staaf
    Yes, isn't that odd? I don't know for sure, but here's my best guess of the etymological history:
    1. Person finds argonaut, names it nautilus.
    2. Person finds nautilus, says hey, this looks just like the other thing called a nautilus, let's call it a nautilus too.
    3. People realize argonauts and nautiluses are quite different. They add adjectives to distinguish the "paper nautilus" from the "chambered nautilus."
    4. Someone realizes that someone else had a different name for the argonaut all along (to wit, argonaut)--this happens all the time in naming things.
    5. Because using adjectives all the time is annoying, they decide to switch to argonaut for the paper nautilus, and just use nautilus for the chambered nautilus.
    I could be all wrong, though.
    Seems plausible. I know that sort of thing happens all the time in mathematics. (-: