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Earth Science

Eight-Armed Animal Preceded Dinosaurs 211

Posted by CmdrTaco
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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Eight-Armed Animal Preceded Dinosaurs

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  • FSM (Score:5, Funny)

    by Alaren (682568) on Wednesday November 05, 2008 @12:15PM (#25643471)
    Check those noodly appendages... intelligent design indeed!
  • by MisterSquirrel (1023517) on Wednesday November 05, 2008 @12:19PM (#25643565)
    Eight-armed, in the sense that a starfish is five-armed. Not quite as sci-fi weird as the headline might sound.
    • by Kanasta (70274)

      Kinda like our 20 armed jellyfish eh?
      Looks a bit small to be called a 'creature'

    • Re: (Score:3, Insightful)

      by lpq (583377)

      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...

  • 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 @12:35PM (#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 butterflysrage (1066514) on Wednesday November 05, 2008 @12:43PM (#25644261)

        what does God need with a starship?

      • Re: (Score:3, Insightful)

        by pete-classic (75983)

        For an instant I was upset that you spoiled it. That feeling was immediately washed away by gratitude.

        Thank you for sparing me from reading this.

        -Peter

      • The greatest thing about the Rama series is the sense of scale that it inspires. You get a sense of adventure in reading the book, and that is a rare gem.

        In spite of its flaws, I can recommend.

        • by TeknoHog (164938)

          Seconded. I'm a big fan of classic, hard SF in the style of Clarke, and this series is one of my favourites. Besides, the ending makes it pretty clear that the Christian explanation is just one of the possible interpretations. IIRC, each of the characters in the book receives an ending they believe in.

          However, Gentry Lee wrote another series of books in the Rama universe, namely Bright Messengers and Double Full Moon Night, which was mostly a disappointment to me. For one thing, the Christian references

      • by Alsee (515537)

        Then, in the fourth volume, Lee reveals that the mysterious aliens whose starship humans had boarded were, in fact, angels serving the Christian God.

        Holy chit.

        By some quirk of fate I stopped at the third book, Thank-Xenu!

        -

    • by Gilmoure (18428)

      8 legged spiders? Are you mad?!!!

    • by jgrahn (181062)

      Sounds similar to the octospiders featured in the Rama sequels.

      Radial symmetry, amoeboid, found as fossils ... I'm more reminded of H. P. Lovecraft's At The Mountains of Madness. Bad news for all albino, cave-dwelling penguins.

  • by peter303 (12292) on Wednesday November 05, 2008 @12:22PM (#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 @12:28PM (#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 @12:30PM (#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 @01:11PM (#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 LanMan04 (790429)

          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.

          Correct. Newborn starfish (maybe brittle stars as well?) have bilateral symmetry and only later turn into the radially symmetric creatures we know and love. So, chances are there is some advantage to the starfish shape, even over bilateral symmetry.

      • by Five Bucks! (769277) on Wednesday November 05, 2008 @02:30PM (#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]

      • ... the arms and legs at least sprout 5 fingers and toes.

        Not necessarily true for all tetrapods (mammals, birds, dinosaurs, lizards, amphibians, etc.). Some digits are lost or greatly reduced on limbs of some species. Occasionally, a six-fingered mutant is born.

        The earliest tetrapods commonly had from four to eight digits on their fore-limbs and hind-limbs. This corresponded to the ancestral lobe structure of their immediate fishy predecessors. This settled out when the five-digited tetrapods turned out to be most successful.

      • I've been pondering the five fingers/toes. Your upper arm and your thigh have one bone each. Forearm and lower leg have two bones. Then in your wrist and ankle, a layer of three bones, and then four. Then finally the five digits.

        Is there anything to this pattern?

      • Indeed. This kind of 5-fold symmetry seems very common in organisms - both plants and animals.

        It is quite different to the even-numbered symmetries one sees in non-organic forms.

        Often, the quickest way to visually distinguish between organic or inorganic natural structures is to consider the symmetry.

        Conjecturing wildy, perhaps it is nature's way of encoding genetic information in fractal form?

    • by Moraelin (679338) on Wednesday November 05, 2008 @02:18PM (#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 @12:24PM (#25643727)
    So I would take it that these creatures would have invented personal deoderant before the wheel?
    • Re: (Score:2, Insightful)

      by CDMA_Demo (841347)

      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 @12:25PM (#25643741)
    The passing of our 8 legged, sea dwelling, Gondwanalandish ancestral overlords
    • Re: (Score:3, Funny)

      by Geak (790376)

      "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 @12:25PM (#25643757)

    Cthulu--the ancient one!

  • by prestomation (583502) on Wednesday November 05, 2008 @12:31PM (#25643917)

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

  • I knew it (Score:3, Funny)

    by Andr T. (1006215) <andretaff@noSpam.gmail.com> on Wednesday November 05, 2008 @12:32PM (#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 @12:32PM (#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 @12:39PM (#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)

      by Hoplite3 (671379)

      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.

    • by LanMan04 (790429)

      I'm being dead serious: Can you show me some examples of macroscopic animals that aren't symmetric in some way? I'm curious, I've never heard of any.

      • by RedBear (207369)

        I'm being dead serious: Can you show me some examples of macroscopic animals that aren't symmetric in some way? I'm curious, I've never heard of any.

        Fiddler crabs? But they're only partially asymmetrical. Don't know of any others. But 550 million years ago there were some pretty bizarre lifeforms living in the ocean where it was probably a lot easier to be asymmetrical and survive.

        Once animals needed to swim, walk and fly in any specific direction bilateral symmetry would have been a significant advantage over anything else. Most animals with radial symmetry don't move very quickly even in the water. On land radial symmetry would be very difficult to us

  • by Weh (219305)

    cthulhu?

  • I wonder whether they would have invented aerosol deodorant before the wheel.

  • So big whoop. They were like 25 cents in gumball machines. You'd throw them at windows and they'd slowly crawl down. Can't wait til someone unearths a gummy bracelet or a Swatch watch...
  • by Michael Woodhams (112247) on Wednesday November 05, 2008 @04:20PM (#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.

    • by RedBear (207369)

      My thoughts exactly. The impressions of the arms are so evenly spaced that I would suspect they were joined together by some kind of membrane that was probably used for swimming propulsion. When was the last time you saw a fossil of any animal with thin extremities where all the appendages were laid out so neat and orderly?

      On the other hand I once saw something very similar in a tank at a small museum somewhere in Kaohsiung, Taiwan. It too had several spiraling arms around its base and a body about half an

    • Re: (Score:3, Interesting)

      by GleeBot (1301227)

      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.

  • Octopuses are going to be pissed that missed the 8 arms frist prost.

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