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Education Science

Dinosaur Forces Rethink Of Flight's Evolution 328

Posted by Zonk from the always-fun-to-think-about-it dept.
gollum123 writes "The BBC reports that a small dinosaur with a long, slender snout and wing-like limbs is forcing a rethink on bird evolution." From the article: "The 90 million-year-old reptile, called Buitreraptor gonzalezorum, belongs to the same sickle-clawed group of dinosaurs as Velociraptor and feathered dinosaurs from China. It may provide tantalising evidence that powered flight evolved twice. One theory suggests the lineage of dinosaurs the new animal belonged to, the dromaeosaurs, originated in the Cretaceous Period (144 to 65 million years ago). But this discovery suggests their lineage can be traced further back in time, to the Jurassic (206 to 144 million years ago), experts say."
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Dinosaur Forces Rethink Of Flight's Evolution More

Dinosaur Forces Rethink Of Flight's Evolution

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  • This just in (Score:3, Funny)

    by antifoidulus ( 807088 ) on Thursday October 13, 2005 @11:17PM (#13788093) Homepage Journal
    Dinosaurs rumored to have had superior grammar skills when compared to slashdot editors!

  • That begs the question .... (Score:5, Funny)

    by slashbob22 ( 918040 ) on Thursday October 13, 2005 @11:21PM (#13788104)
    "small dinosaur with a long, slender snout and wing-like limbs"

    ... who said pigs couldn't fly?

    • Re:That begs the question .... (Score:5, Funny)

      by Acts of Attrition ( 635948 ) on Friday October 14, 2005 @02:18AM (#13788653)
      Better question: What the heck is a dinosaur?
      I can't find a mention of them anywhere in my Bible. You folks and your alternative science!

      • Re:That begs the question .... (Score:4, Interesting)

        by Zapdos ( 70654 ) on Friday October 14, 2005 @01:08PM (#13792247)
        Interestingly, the word 'dragon' is used a number of times in the Old Testament. In most instances, the word dinosaur could substitute for dragon and it would fit very nicely. Dinosaurs were called dragons before the word dinosaur was invented in the 1800s. We would not expect to find the word dinosaur in Bibles like the Authorized Version (1611), as it was translated well before the word dinosaur was ever used.

        Also, there are many very old history books in various libraries around the world that have detailed records of dragons and their encounters with people. Such as that of English King Morvidus. Surprisingly, many of these descriptions of dragons fit with how modern scientists would describe dinosaurs, even Tyrannosaurus.

        • Try finding descriptions that fit "how modern scientists would describe dinosaurs" in places other than Creationist sites. Provide links, then watch how someone familiar with dinosaur taxonomy shreds the supposed support for (echo)"Dinosaurs Amongst Men"(/echo).
    • Pigs could never fly. Look at them! They're about as aerodynamic as a bumblebee.

      >_>

      Er, bad example.

    • Re:That begs the question .... (Score:5, Informative)

      by drafalski ( 232178 ) on Friday October 14, 2005 @07:57AM (#13789730)
      Actually, it raises the question. Begging the question [wsu.edu] is a formal logic term that does not mean what most people seem to think.

      Text from the link:
      An argument that improperly assumes as true the very point the speaker is trying to argue for is said in formal logic to "beg the question." Here is an example of a question-begging argument: "This painting is trash because it is obviously worthless." The speaker is simply asserting the worthlessness of the work, not presenting any evidence to demonstrate that this is in fact the case. Since we never use "begs" with this odd meaning ("to improperly take for granted") in any other phrase, many people mistakenly suppose the phrase implies something quite different: that the argument demands that a question about it be asked--raises the question. If you're not comfortable with formal terms of logic, it's best to stay away from this phrase, or risk embarrassing yourself.
      • Can we get the slashdot editors to make some script that automatically rejects posts with the phrase "begs the question"? People who know how it should be used don't use at all, so every usage is always wrong.
  • Does this mean that the chicken in the freezer is even older than the package says? ;-)

  • Insect (Score:5, Interesting)

    by doubtless ( 267357 ) on Thursday October 13, 2005 @11:27PM (#13788126) Homepage
    Don't we already have two different types of powered flights? Birds, and Insects?

    • Re:Insect (Score:5, Insightful)

      by M. Baranczak ( 726671 ) on Thursday October 13, 2005 @11:31PM (#13788146)
      #3: bats

    • Re:Insect (Score:5, Informative)

      by rolfwind ( 528248 ) on Thursday October 13, 2005 @11:41PM (#13788181)
      I don't know if Hummingbird can be categorized as a different model of flight but:

      http://oregonstate.edu/dept/ncs/newsarch/2005/Jun0 5/hummingbird.htm [oregonstate.edu]

      They can hover, fly backwards/forwards, or even upsidedown.

      • Re:Insect (Score:3, Informative)

        by AndersOSU ( 873247 )
        sheesh link an article that explains cool flow visualization techniques, on an interesting subject, and draws interesting conclusions...

        But not a single picture. So I did my own digging. Here's one. [eurekalert.org] And another. [futurefeeder.com]

    • From a Paleo Class (Score:4, Informative)

      by Wyatt Earp ( 1029 ) on Friday October 14, 2005 @12:10AM (#13788283)
      In mammals and reptiles
      Passive flight
      a. Gliding
      b. Parachuting;
      Soaring
      Powered flight

      Bugs
      The first animals to take to the air under control.
      Carboniferous
      The only flying creatures that evolved flapping flight without sacrificing limbs to form the wings.

      Parachuting can evolve in animals with rather low metabolic rates.
      It does not require the high metabolic rate of birds and bats, which have powered flight.
      Late Permian reptile Coelurosauravus
      Bones jointed for folding

      No gliding lepidosaur is known from the fossil record after the Triassic, so the living lizard Draco which also uses elongated ribs to support an airfoil, must represent yet another independent evolution of gliding

    • No Kidding. Evolution isn't a line slanting upward (Score:5, Insightful)

      by ianscot ( 591483 ) on Friday October 14, 2005 @08:01AM (#13789756)
      There's nothing surprising about a trait evolving many different times. The idea that organisms are moving from a more primitive state toward something more advanced is basically all there is to the idea that flight should only have evolved once.

      Knowing that things have branched more than once for a given trait isn't just interesting for paleontologists, either. For example, the group of flat worms that include modern tapeworms has evolved parasitism several different times over its history. Knowing that it didn't just happen once lets us find close living relations of tapeworms that aren't parasitic -- so we can develop treatments for tapeworms much more easily, because a lab doesn't need to deal with test worms that are paired with host animals. Viola, better medicines against tapeworms.

      It's intuitive to think flight is somehow special because it places extreme physiological demands on the animals that use it, but it's just like any other evolutionary trait. Life is fertile, time is deep. That dinosaurs would maybe develop the trait twice isn't astonishing at all. They were around for a long time, and they maybe had some basic traits (bones with the potential for bird-like light internal structure or something) that made it more likely.

    • why, just because we know so little about bird origins and so much about pterosaurs, do we keep forgetting to mention them as flyers?

      sheesh...

      you'd think a creature with a 20 foot wingspan [bbc.co.uk] wouldn't be forgotten about so easily when talking about flyers.

  • Hmm... (Score:3, Interesting)

    by evil agent ( 918566 ) on Thursday October 13, 2005 @11:33PM (#13788149)
    This might explain why emus are only found in Australia, which became separated from Gondwana.
    • And they independently evolved beaks?

        Emu are true birds, and related (albeit not terribly closely) to ostriches and rheas (which are not found in oceana) as well as kiwis and cassowaries (which are native to oceana). They are birds, not an independently evolved lineage of dinosaurs.

  • No you can't recover the DNA (Score:5, Informative)

    by sam_handelman ( 519767 ) <samuel DOT handelman AT gmail DOT com> on Thursday October 13, 2005 @11:33PM (#13788152) Journal
    Since this comes up in every slashdot story on dinosaurs, no, Jurassic Park is not possible -

      Fossilization occurs when carbon atoms are exchanged for silicon. There is a very high energy barrier to this chemical event - so it happens extremely slowly, over millions of years.

      Nucleic acids, the building blocks of DNA, spontaneously decay (even in the absence of bacteria or degrading agents). The spontaneous decay of DNA is very slow by most standards - if kept under the proper conditions a DNA molecule can last for millennia. However, this spontaneous decay is a great deal faster than the exchange of carbon and silicon, especially when you consider that the carbon and silicon must exchange over the surface area of the sample (for example a bone several inches thick fossilizes very slowly from the outside in,) while the DNA is decaying continuously in the marrow. So, for a fossil millions of years old, even if you managed to recover something that looked like a nucleic acid base, it would be decayed to the point that the information content is completely gone.
    • The problem with this is that Jurassic Park didn't get its DNA from bone marrow, but from insects trapped in Amber.

      I'm not sure how much that changes things, but just pointing out that in the book they do not get it from bones!

    • Why not? (Score:5, Insightful)

      by node 3 ( 115640 ) on Friday October 14, 2005 @12:38AM (#13788380)
      What you've said implies that it's not impossible, just really, really difficult, and extremely unlikely, but you haven't made the case that it's "not possible".

      They've found fossils with traces of blood, skin, flesh and feathers.

      In terms of half-life, there's got to be some "dino-dna" around somewhere right now. At least, given a large enough mass of extant dinosaur remains.

      The real question is just how much raw dino-mass it will take before any usable DNA can be expected to be found. Perhaps it would take many times more mass than that of every dinosaur that ever lived, but perhaps it's small enough that it's probable that in some museum somewhere is a realistically findable and usable strand of DNA.

      I most certainly do not know the answer to that, but I'm not convinced you do either, and I suspect are just promoting as fact something that is more a belief on your part without any serious calculation to back it up.

      • Re:Why not? (Score:3, Interesting)

        by Anonymous Coward
        good post.

        And you don't even need to find a single strand of dna... lots of pieces will do. It just takes computing power to calculate the original un-broken strand, and then work in the lab to recreate (I'm not saying it's easy).

        Example: you can probably guess what these three dna strands came from:

        - srethinkoffl
        - offlightsevolution
        - dinosaurfor
        - urforcesrethin
        - sevolut

      • Re:Why not? (Score:5, Interesting)

        by sam_handelman ( 519767 ) <samuel DOT handelman AT gmail DOT com> on Friday October 14, 2005 @01:25AM (#13788508) Journal
        Well, I didn't do the calculations myself:
        "However, kinetic calculations predict that
        small fragments of DNA (100-500 bp) will survive for no
        more than 10 kyr in temperate regions and for a maximum
        of 100 kyr at colder latitudes owing to hydrolytic damage
        (Poinar et al. 1996; Smith et al. 2001). Even under ideal
        conditions, amplifiable DNA is not thought to survive for
        longer than 1 Myr." - see reference below

          As to your proposal, if I make enough random DNA out of monomers, eventually one of those artificial chains will form a complete dinosaur chromosome. How, exactly, do you propose that I identify this perfect chromosome from among the population in my (absolutely enormous) sample?

          Reference:
        http://www.journals.royalsoc.ac.uk/openurl.asp?gen re=article&eissn=1471-2954&volume=272&issue=1558&s page=3 [royalsoc.ac.uk]

          For what you *can* do with fossil DNA, read this:
        http://www.pnas.org/cgi/content/full/102/39/13783 [pnas.org]
        • Even under ideal conditions, amplifiable DNA is not thought to survive for
          longer than 1 Myr.

          "not thought to" is different from "not possible", although I'd accept adequately long odds as being essentially the same as "not possible".

          It would seem to me that the idea of a half-life would apply (although not necessarily linearly), in that after so much time, there would be half the original DNA left, and so on, so that even after hundreds millions of years there would be some amount of intact DNA around, given
        • How, exactly, do you propose that I identify this perfect chromosome from among the population in my (absolutely enormous) sample?

          It's really simple actually. It's the same way we sequence genomes. Shotgun style. You have a whole bunch of samples and they all degrade in different ways. As long as most of your breaks are overlapping you can piece everything back together.

          ----X----X----
          --X---X----X--
          In this simple diagram you can see how I wouldpast together the overlapping regions.
    • What if they found dinosaurs trapped and preserved in ice, like woolly mammoths have been?
    • Fossilization occurs when carbon atoms are exchanged for silicon.

      Well, of course they didn't use a fossil in Jurassic Park, they used a mummy. Even the Wikipedia article makes this confusion. Old and/or preserved does not mean fossil. Fossil is as you have stated, the replacement of the original tissues by a mineral (say, calcium carbonate or anything else capable of forming sedimentary rock. You don't often find large quantities of silicon in solution. Lots and lots of carbon though, as well as the carbon

  • Dinoaves (Score:4, Interesting)

    by Anonymous Coward on Thursday October 13, 2005 @11:33PM (#13788154)
    We just need to accept that they aren't "terrible lizards" but "terror birds," and change the name from dinosaurs to dinoaves. The name has already been changed from 'dragons', so I think we can manage this.

    Which came first, the chicken or the dromeaosaur?

    And flight has three other instances, if you don't count flying squirrels and gliding snakes: both major kinds of bats, and the monotreme ptero"saurs" - they were warm-blooded furry and laid eggs. That is a monotreme, like the spiny echidna and duck-bill platypus.

    • Re:Dinoaves (Score:2, Interesting)

      by hywel_ap_ieuan ( 892599 )

      ...ptero"saurs" - they were warm-blooded furry and laid eggs. That is a monotreme, like the spiny echidna and duck-bill platypus.

      Not really. You've picked two of the defining features of monotremes, but it takes much more than that to group creatures together. And the "fur" from pterosaurs is almost certainly very different from mammalian hair.

      Pterosaurs are a group related to dinosaurs. They're both part of the Archosaurs - a group that contains modern crocodiles and birds and their extinct relatives.

  • birds [wikipedia.org], bats [wikipedia.org], insects [wikipedia.org], spaghetti monsters [wikipedia.org]....yup!

  • Flight Evolved Twice? (Score:5, Informative)

    by BarryHaworth ( 536145 ) on Thursday October 13, 2005 @11:36PM (#13788163) Homepage
    From the posting:

    It may provide tantalising evidence that powered flight evolved twice.

    As I recall, powered flight has evolved independantly a number of times.

    Insects

    Birds

    Pterosaurs

    Bats

    and if I not mistaken, fruit bats evolved flight separately to insect-eating "true" bats. That's at least four if not five times.

  • Now that's what I call 'intelligent design'! (Score:4, Funny)

    by RLiegh ( 247921 ) * on Thursday October 13, 2005 @11:45PM (#13788200) Homepage Journal
    make a few throw away prototypes before marketing the real thing. Fooey to all those 'evolutionists' and their 'science', I say!

  • Nah (Score:5, Funny)

    by ColaMan ( 37550 ) on Thursday October 13, 2005 @11:47PM (#13788203) Journal
    It's just God messing with our heads.

    Didn't you read that bit in the bible? In Genesis? In that footnote 4 or 5 pages in?

    "And the Lord brought forth the remains of many, many varied animals and plants, different to what existed on the newly-fashioned earth. And lo, He crafted a fossil record that suggested they did indeed exist far in the past, and planted it so that men of Science, with their need to understand with Hard Facts and Reason and Logic, would have something to explain the Creation with. For the Lord looks after all His children, even those of little Faith."

    It's all in there people. You just have to read and interpret it a little bit.
    And change a few words here and there. And possibly fragment and rearrage sections. But it's all in there.

  • Big Bird (Score:2, Informative)

    by obidonn ( 590065 )
    That article is horrible, and the posting is also not so good. Here's a link to the press release from the Field Museum in Chicago, where one of the co-authors of the Nature article works:
    http://www.fieldmuseum.org/museum_info/press/press _sinovenator.htm [fieldmuseum.org]

    And here's a link to a non-subscription site that's carrying the Chicago Tribune's article, which a lot of outlets seem to be carrying because it compares the dinosaur to Sesame Street's Big Bird:
    http://www.newsday.com/news/health/chi-0510130118o ct13, [newsday.com]

  • Not Flight, Intelligent Falling (Score:5, Funny)

    by Bob9113 ( 14996 ) on Friday October 14, 2005 @12:35AM (#13788369) Homepage
    Evolution is nothing but a theory, just as is gravity. Theory means "not true". The real basis for flight is God's divine will expressed through specific cases where He suspends Intelligent Falling. [theonion.com] Flight is one of the most clear examples that proves Intelligent Falling, and that the "theory" of gravity is just bunk foisted on us by a bunch of scientists who want to destroy God.

    • Re:Not Flight, Intelligent Falling (Score:2, Funny)

      by Anonymous Coward
      You joke, but gravity is just a theory. Why is it so much weaker than magnetism? Perhaps because a creator wanted us to be able to walk. I have a site devoted to this http://www.teachthecontroversy.com/ [teachthecontroversy.com]
      • You joke, but gravity is just a theory.

        You are using the wrong definition of theory [stephenjaygould.org]. Nothing is ever "just" a theory; a theory is the very pinnacle of truth, explaining numerous facts, data, and observations.

        I was reading your site and thinking to myself, "Okay, so this is different than the usual take on the universe from creationists..."

        And then I hit on the following line, and I realized you're taken in with the frauds just like the rest of your ilk.

        The answer is as clear here as it is in dealing with
    • "That wasn't flying! That was... falling with style!"

    • Re:Not Flight, Intelligent Falling (Score:5, Informative)

      by Bob9113 ( 14996 ) on Friday October 14, 2005 @03:31AM (#13788809) Homepage
      Flamebait?!? Informative?!? Correcting my definition of "Theory"?!? Wow. I am astonished. OK, I know 99% of you got it, but for that "special" 1%, umm, it's a joke. Laugh. If you can't laugh at Intelligent Falling, you're taking it waaaaaay too seriously.

      And if you're actually serious about the flamebait mod, and you're now thinking, "but it is serious, ID as scientific theory is a serious subject," you're wrong. It is not a scientific theory. I'm not saying it isn't true(*) so don't get your panties in a bunch. I'm just saying it is not science. Science is the search for natural explanations to non-intuitive phenomena. Scientific theories make predictions that are disprovable(**). ID is a supernatural explanation to a non-intuitive phenomena which does not make predictions and is not disprovable. As such, ID is philosophy of religion, or mysticism, or faith, or whatever term you feel is appropriate for the study of supernatural explanations to non-intuitive phenomena. Not a better field, not a worse field, not more true, not less true, just a different field of study than science.

      So get over it. Laugh. Or are you afraid that the shared behaviour of laughing will betray your common ancestry with the great apes? Yes, ferchrissakes, that's a joke too.

      Sorry about the "ferchrissakes" thing - I didn't mean to blaspheme. The editors of that paragraph have been sacked.

      * Typically supernatural explanations are inherently not disprovable, and this is the case with ID. Any scientist worth his salt will not say that something is false if it can't be disproven. Listen closely next time, you'll not hear a serious scientist say "ID is not true." The scientists aren't trying to kill God, they're just working in a different field than philosophy of religion.

      ** For a great example of hardcore science-like research that is not science, check out game theory. It is a fascinating area of economic research, but since it can only be used to analyze and not predict, it is not science. There's a very good article on the topic here [businessweek.com].
      • Scientific theories make predictions that are disprovable

        I've always thought that this is a poor choice of words to explain scientific theories to the masses. How about just plain old "testable"? Everyone knows what that means.
        ID is not testable. Scientific theories are.

  • When did the dinosaurs develop a military, and what happened the first time they thought about the evolution of flight?

  • Bird/Dinosaur (Score:2, Informative)

    by Belseth ( 835595 )
    One massive problem with the theory of birds evolving from dinosaurs is the date for birds keeps going backward and very early feathered reptiles have been found. The solution seems obvious. Birds, Mammals and dinosaurs evolved at roughly the same time. The mammals of the time were more reptile like but so were the birds. If birds came from dinosaurs birds should have evolved at the end of the Cretaceous not at the begining of the Triassic as the earliest bird accestors seem to show up. The similarities app

    • Re:Bird/Dinosaur (Score:4, Informative)

      by Conanymous Award ( 597667 ) on Friday October 14, 2005 @05:22AM (#13789101)
      If birds came from dinosaurs birds should have evolved at the end of the Cretaceous not at the begining of the Triassic as the earliest bird accestors seem to show up.

      Not at all. Birds, capable of real powered flight, are known from lower Cretaceous already (even upper Jurassic, if you count Archaeopteryx, which might infact come from a relic island population). Check out what has been found and is still being found from Liaoning, China. I study vertebrate paleontology and I'm not aware of any earlier bird-like creatures than middle or upper Jurassic. Can you give a reference? Longisquama might have had feathers (many paleontologists don't agree), but otherwise it's not very bird-like. Feathers might even have been a trait that many reptiles of certain kind had in those times.

      The evidence for birds evolving from dinosaurs (and actually being dinosaurs) is nowadays overwhelming. The anatomical similarities between birds and maniraptoran dinosaurs are as obvious as those of apes and humans. Genera like Buitreraptor (a dromaeosaur) are actually very strong candidates of being secondarily flightless creatures (meaning, their ancestors had the ability to fly but reverted to flightlessness). Also, this new find also makes it clear that an earlier find, Rahonavis from Madagascar, is actually a dromaeosaur, and Rahonavis is generally considered having been capable of flight. Thus, we have a flying dromaeosaur! These are fantastic finds, and our picture of the evolution of birds becomes clearer by every one of them. And it is a very controversial field of study, we are probably still in for quite many suprises in near future. But that's what makes all of this so interesting.
  • > It may provide tantalising evidence that powered flight evolved
    > twice.

    At least three times: birds, bats, and bugs.

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