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Eight-Armed Animal Preceded Dinosaurs

Posted by CmdrTaco on Wed Nov 05, 2008 11:14 AM
from the doc-oc-uber-alles dept.
Garimelda writes "Scientists have discovered what they believe is an eight-armed creature which colonized a large section of the world's oceans over 300 million years before the first dinosaurs emerged."
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  • FSM (Score:5, Funny)

    by Alaren (682568) on Wednesday November 05 2008, @11:15AM (#25643471) Homepage
    Check those noodly appendages... intelligent design indeed!
  • by MisterSquirrel (1023517) on Wednesday November 05 2008, @11:19AM (#25643565)
    Eight-armed, in the sense that a starfish is five-armed. Not quite as sci-fi weird as the headline might sound.
    • Re: (Score:3, Insightful)

      I dunno...eight arms? soft? like a pussy cat...hey, lets call it an octopus! Who knows...some day maybe someone can get a Ph.D. studying these creatures -- we could call 'em Doc-Oc...

      • by Anonymous Coward on Wednesday November 05 2008, @12:18PM (#25645021)

        Erm... did many people interpret it as such?

        I did. It's because of the "preceded dinosaurs" which made me think it was eight-armed vertebrates, for about two seconds. There's no reason to say "preceded dinosaurs" when it was significantly before dinosaurs and had nothing to do with them. You could say they preceded humans. It's just silly and confusing. It turns out these fossils are twice as old as dinos.

        A better word would be "predate" which doesn't imply a close correlation in time.

      • by theaveng (1243528) on Wednesday November 05 2008, @12:22PM (#25645133)

        This animal is more like a hydra with multiple tentacles but extremely small and simplistic in design.

        BTW there were LOTS of creatures that came before the dinosaurs.

        There were the Cambrian creatures, followed by the Synapsids that were huge reptile-like creatures that dominated the planet until they were eventually replaced the dinosaurs. The Synapsids then evolved into mammals - http://en.wikipedia.org/wiki/Synapsid [wikipedia.org] For more info see the BBC's "Before the Dinosaurs"

  • Ladies and gentlemen, the plot to next year's summer movie flop.
  • Sounds similar to the octospiders featured in the Rama sequels. Okay, not really, I just felt like throwing out references to pop science fiction.

    • Re:Octospiders (Score:5, Interesting)

      by CRCulver (715279) <crculver@christopherculver.com> on Wednesday November 05 2008, @11:35AM (#25644037) Homepage

      Sounds similar to the octospiders featured in the Rama sequels.

      Oh god. I've been trying to forget those for over ten years now, and now you've brought all the horror back. In case anyone doesn't know, Clarke's Rendezvous with Rama [amazon.com] is a science fiction classic that only gets better with age. The sequels made in collaboration with Gentry Lee, however, have no touch of Clarke's genius. It's suggested that Gentry Lee penned them all by himself, and his interests were peculiar indeed. The third volume of the series has some of the most ridiculous sex ever found in science fiction, a genre already infamous for bad erotic scenes. Then, in the fourth volume, Lee reveals that the mysterious aliens whose starship humans had boarded were, in fact, angels serving the Christian God. Though why an omnipotent deity works through robots and subjects races to agonizingly slow slower-than-light travel is never explained.

  • by peter303 (12292) on Wednesday November 05 2008, @11:22AM (#25643671)
    Maybe four limbs gives you more bang for the buck in terms of the energy of development and survival locomotion. However insects and relatives have been more creative with all even numbers - 2, 4, 6, 8 and dozens.
    • by peter303 (12292) on Wednesday November 05 2008, @11:28AM (#25643825)
      I recall people studying the evolution of locomotion by allowing any kind of movement- walking, tumbling, slithering, wheels, etc. Computer programs "evolve" trying random mutations and look at resulting locomotive efficiency. Some clever, unexpected solutions result which you dont see in nature. I forget the reference, but may be associated with the Sante Fe Artificial Life Institute, etc.
    • by OzPeter (195038) on Wednesday November 05 2008, @11:30AM (#25643877)
      I have always wondered where we got our 5-fold symmetry from. Our core body sprouts 5 elements (head, 2 arms and 2 legs), and the arms and legs at least sprout 5 fingers and toes.
      • Re: (Score:2, Interesting)

        The basic mammalian model, I always thought, was a 6-element system - most mammals have a tail, even some humans are born with one, albeit vestigial.

      • by Bowling Moses (591924) on Wednesday November 05 2008, @12:11PM (#25644863) Journal
        We don't have 5-fold symmetry. We're bilaterally symmetric [wikipedia.org]; we have a top, bottom, left, and right. A starfish has a top and bottom, but no left or right. For what it's worth, not even a five-armed starfish has exactly 5-fold symmetry. They are considered radially symmetric, but are thought to have evolved from bilaterally symmetric organisms and have some structures that show this.
      • by Five Bucks! (769277) on Wednesday November 05 2008, @01:30PM (#25646623)

        Tetrapods don't quite represent 5-fold symmetry.

        Think of the tailbone to top-of-skull as a single axis, with two sets of limbs poking out along the axis.

        This developed from the pelvic and pectoral girdles of Sarcopterygians.

        Basically, the whole vertebral column from tail to cervical vertebrae is the principle axis with limbs branching from it. Split down the middle of the principle axis, the body (for the most party) is a mirror image. Thus, two-fold symmetry. Bilateralism.

        Tetrapodia [wikipedia.org]
        5-Fold symmetry [wikipedia.org]

    • by Moraelin (679338) on Wednesday November 05 2008, @01:18PM (#25646391) Journal

      1. Well, you have to also realize that different environments might favour different configurations. For example an octopus doesn't use its noodly appendages in the same way as you use your legs, and not even like a fish uses its fins.

      Each is optimized for its particular use. It's safe to assume that for a fish that particular tail and fin configuration is good, because it evolved several times from something different to that exact configuration. E.g., dolphins evolved to the same scheme, but so did Ichthyosaurs, Plesiosaurs and Mosasaurs, plus a few of their relatives and ancestors. There are two different configurations of four legs which evolved into such a fish-like configuration that Ichthyosaur skeletons were first believed to be fish. So it's safe to assume that for that style of swimming, a fish-like configuration is optimal, and indeed better than four legs or even than two legs.

      Two legs vs four legs also seems to be not that clear cut. The two-legged configuration evolved independently more than once, so it must have _some_ advantages. E.g., all dinosaurs are descendants of a two-legged ancestor. Some, however, returned to four-legged afterwards. Some evolved into birds instead. So again it's probably safe to say that each is good... for a given environment.

      Insects are a funny case, because again they're used differently than you use your legs. Insect legs are autonomous. Each leg has its own autonomous "controller", or rather its own mini-brain. The insect's head just gives an order like "forward" and all legs independently start doing the movements for moving forward. That kind of a wiring would be totally unfit for bipedal use. Heck, even four would be more miss than hit. So an insect must necessarily have a larger number of legs. For the way an insect is built, really, six legs are good, two legs are bad.

      2. But even that is over-thinking it, because the little guys in TFA didn't actually have arms or legs like you. They were really jellyfish with 8 long tubular appendages. There are no muscles there or bones or exoskeleton or anything usable for locomotion at all. The whole thing was really two thin layers of cells, little more than a microbial film, with an amorphous jelly in between. The "arms" were probably more to give it more surface and reach from which it can absorb nutrients, than for anything else.

      We're talking _very_ primitive multi-cellular life forms.

  • by UnknowingFool (672806) on Wednesday November 05 2008, @11:24AM (#25643727)
    So I would take it that these creatures would have invented personal deoderant before the wheel?
    • Re: (Score:2, Insightful)

      According to The Guide, it was the Jatravartids who were "unique", and since The Guide predates Ediacaran period, it is more likely to be correct (unless life itself is guilty of being neither beautiful, nor true).

      Plus, if these newly discovered creatures had 8 limbs, they'd be similar to Octopuses (or octopi/octopodes) who are not known to use deodorants (and instead use a foul smelling chemical to avert predators). Thus, since Octopuses are not known to invent deodorants it is less likely that Eoandromeda

  • by OzPeter (195038) on Wednesday November 05 2008, @11:25AM (#25643741)
    The passing of our 8 legged, sea dwelling, Gondwanalandish ancestral overlords
    • Re: (Score:3, Funny)

      "According to palaeogeographic reconstructions, South China and South Australia were close to each other at the time, belonging to a supercontinent called Gondwana," says lead author Dr Maoyan Zhu.

      I think the more important discovery here is time travel. How else would he know the continent was called Gondwana 300 million years ago? Also suprising is that these 8 legged creatures were able to tell him that. I don't think humans existed back then.

  • by catdevnull (531283) on Wednesday November 05 2008, @11:25AM (#25643757)

    Cthulu--the ancient one!

  • by prestomation (583502) on Wednesday November 05 2008, @11:31AM (#25643917)

    .....someone played Spore a bit too much...

  • I knew it (Score:3, Funny)

    by Andr T. (1006215) <andretaff AT gmail DOT com> on Wednesday November 05 2008, @11:32AM (#25643933)

    ...they describe other early living things that looked like leaves, shells, stars and something almost akin to a peace symbol.

    Damn hippie fossils!

  • by Daniel Dvorkin (106857) * on Wednesday November 05 2008, @11:32AM (#25643957) Homepage Journal

    Given the time scales involved, that's kind of like saying "Alexander preceded Napoleon" -- I mean, it's true, but it leaves out a whole lot that happened in between.

    Oh, never mind. The past is telescoped. There's old stuff (things that happened before my parents were born) older stuff (George Washington and other guys in funny clothes) very old stuff (King Arthur and Robin Hood) extremely old stuff (cavemen and dinosaurs) and, apparently, incredibly old stuff (before cavemen and dinosaurs -- who knew?) No point in asking people to maintain a sense of persepective.

  • by timholman (71886) on Wednesday November 05 2008, @11:39AM (#25644135)

    To me, the most interesting aspect of these early, pre-Cambrian-Explosion fossils was that bilateral symmetry (which is the norm for practically all animal life today) was nothing special. You had lots of organisms that were radially symmetric or just plain asymmetric. Whatever mass extinction event wiped out the majority of the Ediacaran biota gave a foothold to the bilaterally symmetric ancestors of modern animal life, which then dominated the Cambrian Explosion. It is just a fluke of evolution that we are not radially symmetric or asymmetric. Shades of Niven & Pournelle's Moties!

    • Re: (Score:3, Insightful)

      I think bilateral symmetry could be shown to have advantages out-of-water. In the ocean, movement in three dimensions is common, and radially-symmetric designs are reasonable. But on land, movement is confined (mostly) to a plane, so the extra symmetry doesn't help an organism very much. There'd be a lot of wasted tentacles.

      Like an octopus bar on $1 tequila night.

  • cthulhu?

  • by Michael Woodhams (112247) on Wednesday November 05 2008, @03:20PM (#25648475) Journal

    Those 'limbs' are in an exceptionally regular spiral pattern. If you fossilized an octopus, you'd expect the limbs to be all crossed over and tangled up. I'm guessing that those 'limbs' couldn't move independently, and are more like ridges in a sheet of material.

    • Re: (Score:3, Interesting)

      Those 'limbs' are in an exceptionally regular spiral pattern. If you fossilized an octopus, you'd expect the limbs to be all crossed over and tangled up. I'm guessing that those 'limbs' couldn't move independently, and are more like ridges in a sheet of material.

      More to the point, a soft-tissued creature like an octopus almost never leaves a fossil record. If you find a fossil, it's because of some sort of skeletal structure the creature has left behind, which of course would naturally be rigid. Think of something like an eight-branched exoskeletal structure.