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Science

Fish with Limbs 137

Posted by michael from the stop-poking-me dept.
kpogoda writes "American scientists have unearthed the world's oldest arm bone, a 365-million-year-old fossil that provides key evidence that fish used limbs in water well before animals used them to climb up on land."
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Fish with Limbs More

Fish with Limbs

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  • without reading into the article at all, it sounds to me like good evidence supporting evolution. Yay for science!
    • Religious zealots do not like science, because there is no 'believing' involved. Also Darwinist, being scientists, do not have as extreme prejudice in discussions as religious zealots. Scientists change their pov when they are proven wrong, they do not run away with fingers in their ears like some others do. Has there ever been a creationist in a court of law for telling about the Adam & Eve story?
      • Not to mention the fact that Darwinism and Creationism are not necessarily mutually exclusive. There was an article here [bibledecoded.com] that gives some insight.

        Note: I am not affiliated with the LW church.

        -Bruce
        ---------
        |\|3+85D: f0r t3h r3al 133+ h4x0r5. Those who know will attest! They will agree! They already use it! They will not use annoying hacker-esque stereotypes!
      • That is the largest load of rubbish propoganda. Darwinists are not zealots? Ha! Among Darwinist evolutionists I encounter the greatest zealotry and unwillingness to listen. When I talk to evolutionists in depth, they say that biology doesn't know exactly how evolution occurred, but we do know it occurred because of the fossil record. Yet the fossil record shows no evidence of evolution, and it's claimed this is expected because of the way fossils are formed. How convenient. Stephen Gould said:

        The h

        • What if natural selection does not improve the species? What if all living things were created in their best form, and have been heading downhill since then? Natural selection then plays the role not of improving a species, but of slowing its decline - such that if the power of natural selection was absent, the fall of a species would be hurried. Yet if natural selection was present, the species would still degrade, but at a much slower rate.

          I have no idea who you are, so I'll try to be as cordial as poss
          • When I said an absence of natural selection I was not speaking about reality, but a hypothetical situation. For us to understand what natural selection does, we must be able to imagine what would happen if it did not play a part. You have given no reason why natural selection as we understand it couldn't fulfil the role I proposed (though I'm not the first to propose it).

            What proof have you that natural selection improves a species, rather than just slowing the survival of harmful genes, and reducing di

            • Evolution is the process by which things change because of random mutation and because environments [see: actual environment, other organism, outside events] only allow a subset of the original population to survive.

              Simple.

              • I fail to see what that has to do with countering anything I said.

                After all, if that is the definition of evolution, it says nothing about the common ancestry of all living things, which most people put under the title of "evolution".

                Personally I prefer the definition from talkorigins:

                Biological evolution is a change in the genetic characteristics of a population over time.

                I will not dispute the definition you gave. I still believe that species are degenerating over generations, and that we do not s

                • I'd really like to carry this conversation over something better than slashdot. Too much latency. My definition says everything about the common ancestor, and so does the definition from talkorigins, I suppose.

                  Feel free to IM me, at Ieshan.

                  I'll be on later tonight and some of tomorrow.
                • "species degenerating over generations" ?

                  There is not the slightest piece of evidence, in the fossil record or in zoology to support this.

                  The only reason you believe in this nonsense is because your particular interpretation of the bible tells you that must be the case.

                  (The irony is that this particular interpretation of the Fall is entirely modern: you won't be able to find any proponent of such a view before the 1800s.)

            • > When I said an absence of natural selection I was not speaking about reality, but a hypothetical situation. For us to understand what natural selection does, we must be able to imagine what would happen if it did not play a part.

              That's easy enough: download the code for your favorite genetic algorithm, hack it to replace selection-by-fitness with random selection, and see how well it works.

              > Please define "evolution", as it has different meanings in different contexts and for different things. Q

              • As you've probably noticed, I usually don't reply to you in particular - but this post was most cordial, so I will.

                That's easy enough: download the code for your favorite genetic algorithm, hack it to replace selection-by-fitness with random selection, and see how well it works.

                Thanks for supporting my argument. I already could imagine life without natural selection, but the person I was responding to could not.

                Could you give an example of what you're talking about?

                Certainly. Darwin's finches are the

        • > Ha! Among Darwinist evolutionists I encounter the greatest zealotry

          Zealotry? What's different about these discussions and everything else that goes on on Slashdot? Or anywhere else on the internet?

          > and unwillingness to listen.

          Maybe it's because we've spent the last couple of years patiently explaining what's wrong with your claims and watching others do likewise, only to have you jump in with the same claims again every time the subject comes up.

          > As for zealotry, woe to anyone who quest

        • What if natural selection does not improve the species? What if all living things were created in their best form, and have been heading downhill since then? Natural selection then plays the role not of improving a species, but of slowing its decline - such that if the power of natural selection was absent, the fall of a species would be hurried. Yet if natural selection was present, the species would still degrade, but at a much slower rate.

          This "genetic entropy" concept has a fundamental flaw: if there

          • What's to say this hasn't already happened? Besides, I don't think your example is true. I would reject the claim that insects would be wiped out if "genetic entropy" was true. Insects are hard to find and numerous - far more numerous than their predators, which are hunted by other creatures. The circle of life ;)

            Ultimately I don't believe that the predators of insects are powerful enough to destroy them. This is obvious from reality, and I'm saying that in reality creatures could be devolving. Natu

            • Natural selection would still work to balance things out, as would predators of predators. If a predator feeds off insects, then when the insect population gets low, so would the predators start to die, giving the insects a chance to grow, and so on.

              No, natural selection can't balance out devolution; the more selective pressure there is on a species, the less it would devolve. This is not symmetrical to evolution!

              Evolution would speed up when the selective pressure is high, causing the species to change

              • I now realise that we are talking about two separate parts of darwinist evolution.

                Natural selection can be split into these two functions, for purposes of clarifying this debate:
                1. Selection of existing traits - Darwin's finches are a good example. This is when a creature inherits traits from its parents, but only those that inherit certain traits have a better chance of survival. This has the dual effect of producing rapid speciation and reducing diversity in the gene pool.
                2. Selection of mutations

                • So if we accept the premise that natural selection performs a slowing function (slowing degredation of a species) rather than enhancing it, then we would see the following:
                  1. Rapid speciation - the gene pool would initially be large, and offspring would be selected based on the traits they inherited. This is the faster change you noted when there's high selective pressure

                  I'm sorry, but I still don't get this. The way I see it: if we accept the concept of devolution, meaning the genetic makeup of species w

                  • I'm sorry, but I still don't get this. The way I see it: if we accept the concept of devolution, meaning the genetic makeup of species was perfect to begin with and can only degrade over time; we must also accept that losing bits of these perfect genes is one of the processes by which devolution does its job. If there is no such thing as evolution, all processes that change the genetic markup of a species must be devolutionary.

                    Evolution is a change in allele frequencies in a population. Or, at least one

                    • However, this theory says nothing about the direction evolution takes. Through its overuse in the context of the advancement of a species, evolution is assumed to mean a progression.

                      The question is how you define qualifications like "progess" and "perfection". If progess means "better adapted to the current habitat/environment" then most certainly evolutionary progress is taking place. This however says nothing about the state (of perfection) of the changing environment; which makes evolution and devoluti

                    • The question is how you define qualifications like "progess" and "perfection". If progess means "better adapted to the current habitat/environment" then most certainly evolutionary progress is taking place.

                      Agreed.

                      This however says nothing about the state (of perfection) of the changing environment; which makes evolution and devolution interchangeable in a metaphysical context, but not in a physical/biological context. IOW you can speak of devolution if you (morally) judge the environment to be degrading,

                    • This part confuses me, because I don't know what IOW stands for, and I don't think I have the same definition for evolution and devolution as you. Can you word it another way please?

                      IOW stands for In Other Words :) If we agree that natural selection causes better adaptation to the environment (by adaptation and speciation), we can only describe this as a negative development or as "less perfect" if we think the global environment/world itself is degrading independent of adaptation and speciation. This is

                    • Not sure how long this thread has left, but it's been interesting talking with you.

                      I did already admit such an interpretation is possible, but I think this interpretation raises more questions than the (macro-)evolutionary interpretation does. The loss of diversity by adaptation is not per definition permanent (cross-breeding brings back diversity), and in the case of speciation I can't see how that would count as losing diversity.

                      I'm not sure why you think it wouldn't. In order for speciation to occu

                    • In order for speciation to occur, genetic diversity must be lost. That's what speciation does - more useful genes are selected for in a particular environment under particular selective pressures, and the harmful ones are lost. Allowing the most beneficial ones to dominate most or all of the time.

                      Yes, but speciation does not remove genes from the originating species genepool (it could wipe out the species by competition though), it creates a new species from those useful genes but leaves the originating s

    • I'm Troy McClure (Score:2, Funny)

      by Anonymous Coward
      Hi. I'm Troy McClure. You might remember me from such fish-arm films as "Hugged by a Halibut" and "Atlantis Arm-Wrestling 2003"

  • Late april fool's joke maybe? (Score:4, Funny)

    by Toxygen ( 738180 ) on Friday April 02, 2004 @12:53PM (#8747514) Journal
    After all, it says in the article that the upper arm bone they found was "humerus"!

  • Reminds me of wings (Score:5, Interesting)

    by PIPBoy3000 ( 619296 ) on Friday April 02, 2004 @01:04PM (#8747626)
    One of the typical arguments by creationists is how can evolution make these jumps from legs to fully functional wings. The latest thinking is that there's wasn't a giant leap, but rather a series of gradual steps between limbs that didn't impart flying, but still had some use.

    For example, chickens don't fly very well, but have you ever tried to catch a chicken? Those "vestigial" wings sure impart bursts of speed and the ability to leap over obstacles.

    It's neat to see the discovery of similar intermediaries between swimming and walking limbs. Evolution is an amazing and beautiful thing.

    • Re:Reminds me of EYES (Score:4, Interesting)

      by Baron_Yam ( 643147 ) on Friday April 02, 2004 @01:15PM (#8747701)
      I love the standard creationist line that eyes couldn't have evolved - they must have been planned.

      I once read an excellent rebuttal of that which described how to get from a photosensitive cell to a full eye while each stage had a noticable survival benefit... and then followed up by mentioning that it's happened on multiple seperate occasions in evolutionary history.

      Heh.

      • Re:Reminds me of EYES (Score:5, Interesting)

        by Hater's Leaving, The ( 322238 ) on Friday April 02, 2004 @02:48PM (#8748731)
        "...multiple seperate occasions..."

        Not just that, but _differently_ in each of the major eye types. There's no "animal eye", there are at least 3. (I forget exactly how they're categorised, but they're roughly vertibrate, cephalopod, and creepy-crawly.)

        In particular, our retinas are 'back to front'. It's an flawed design, and that's why we have blind spots -- it's where the nerves leave the inside of the eyeball. If our eyes came about through _design_ then it was _crap_ design.

        God-freaks can take the soft cheese out of their ears now.

        THL.

    • Re:Reminds me of wings (Score:1, Interesting)

      by Anonymous Coward

      The latest thinking is that there's wasn't a giant leap, but rather a series of gradual steps between limbs that didn't impart flying, but still had some use.

      As far as I know, that's not "the latest thinking", but a concept that was established a long time ago. Even when I was a kid back in the 80s, I remember reading about how the origins of flight were thought to be lizards with ever-increasing flaps that allowed them to glide slightly (and, of course, the increased surface area helped them when "sun

    • I see this argument, but its by the less sophisticated creationists. Their main beef is not so much with legs to wings (or fins to arms), but things like scales to feathers. We see animals with scales, we see animals with feathers, we see animals with scales AND feathers. the argument is, where are the animals that are covered with something that's BETWEEN a scale and a feather?

      I think it's a valid question, but I wonder if the problem is with classification, not that these intermediate animals exist or n

      • Re:Reminds me of wings (Score:2, Interesting)

        by Zerth ( 26112 )
        Longisquama had long feather shaped solid scales, although not used for flight. Plus, while not considered in the ancestor path of modern birds, Archaeopteryx had both feathers and scales.

        Feathers don't fossilize well(lack of granularity in the surrounding matrix hides detail such as barbules), so many of the intermediate forms may also not have fossilized cleanly. Some birds who have been found without clear feather impressions have been mistaken for dinosaurs such as Compsognathus.

        Lastly, there's a fe
    • Maybe the fish sank to the bottom requiring great effort to 'float'.
      I could see the use of arms to aid them in staying near the surface, you know, swinging amongst the kelp vines the way Tarzan swung through the jungle?
      Next logical step was use the arms to crawl onto the shore.
    • Genes are the elements of evolution. They duplicate, mutate, recombine and otherwise change with time. Focusing on phenotype to the exclusion of genotype is the wrong approach. While the clues from paleontology are rarely genetic, the genetic case for evolution is overwhelming because the premises are simple and demonstrable. Genes have anatomical and physiological consequences. Genes are subject to mutation. Anti-evolution people have a much harder time making a case against molecular biology and thermodyn
    • There was an video segment on Discovery science about the evolution of insect wings. The basis of the research was based on stonefies [psu.edu] and demonstrated how gills could have evolved into stubs which would not have given flight by themselves, but would have provided enough acceleration for the critter to escape from predators. The arms race between these two species would have forced ever faster acceleration to occur, until being fast enough to make flight possible.
  • That's like saying that because I would like to fly, I'll just imagine/think myself into having wings (and hopefully ALL my descendants will imagine/think the same) and flap my arms so that a few generations down the road there will be a grandchild with more 'wing-like' arms. Now, let's only hope that (s)he doesn't imagine/think [him|her]self into having more normal arms (because that would destroy all my plans)...
    And, to add to the whole difficulty of it all, fish can't plan for the future that way.

    • COMMON MISCONCEPTION (Score:4, Insightful)

      by Kiyooka ( 738862 ) on Friday April 02, 2004 @02:12PM (#8748328)
      Evolution is NOT planned. It has nothing to do with intention. Suppose we lived in a world with increasingly intense sunlight (for whatever reason), so that the darker and thicker your skin/hair pigmentation, the more you resist exposure in the wild. If you have sensitive light skin, you'll get burns everywhere, which may perhaps develop into cancer. In 1000 years, when sunlight is extremely intense, most of the pale sensitive-skinned people are dead, while most of the dark tough-skinned are alive. Did anyone plan this? No. Did dark skinned people think "hey! I'm gonna start developing darker skin to survive better"? No. But the population has just "evolved" darker and tougher sun-resistant skin, like it or not, because the ones that didn't have it died off. It's as simple as that.

      People only talk about evolution as a "shaping force" figuratively. It's in fact nothing but an observation about consequence. It's not some insidious super-power you can will.
      • Now how hard is that to understand? I just don't get the Creationist point of view. It's all about adaptation. You evolve because you need to adapt. Some magical bearded humanoid in the clouds doesn't just say "CHANGE!" and voila we have a different kind of being. It's just silly.
        • Nope, actually, it's all about dying because you couldn't adapt
    • Does your post make any sense? Do you know what Mutation and Natural Selection are. Google is your friend, especially when your high school bio classes were not:

      The second type of mutation is called a micromutation, or a mutation that involves a very small change. An incredibly vast majority of all mutations fall into this category. These mutations can be (and generally are) harmful in effect, but are not drastic changes, but rather fine gradations. Micromutations are what evolutionists discuss when stud

    • "That's like saying that because I would like to fly, I'll just imagine/think myself into having wings... a few generations down the road ..."

      Not at all.

      You can plan evolution. You put yourself, and thousands of like-minded individuals, in an environment which provides a concrete advantage to having a particular trait.

      If the central asian tribes of 10000 years ago had _wanted_ to be shorter and stumpier, then they could have chosen to migrate further north, and then procreate sufficiently such that the

  • Such a positive, evolutionary response (Score:5, Funny)

    by AtariAmarok ( 451306 ) on Friday April 02, 2004 @01:39PM (#8747925)
    fish used limbs in water well before animals used them to climb up on land.

    Such a positive and evolutionary interpretation. It is far more likely that they used the arms to slug other fish.

  • that's quite the fish! (Score:4, Insightful)

    by wibs ( 696528 ) on Friday April 02, 2004 @01:51PM (#8748071)

    an aquatic, salamander-like creature that would have pushed its arms downward to move through shallow rivers, and used them to prop itself up while waiting for prey or to get air.

    sounds like a fish to me!

  • Reminds me of... (Score:4, Informative)

    by FlyingOrca ( 747207 ) on Friday April 02, 2004 @02:50PM (#8748754) Journal
    the epaulette shark:

    http://www.elasmo-research.org/education/shark_p ro files/orectolobiformes.htm
    (scroll down)

    It uses its limbs to "walk" around, and will even "walk" away when threatened rather than swimming (which would be faster, one thinks).

  • story (Score:1, Insightful)

    by sirhc7 ( 652501 )
    Well after reading the article what comes to mind is that considering how old this bone is, we can all be pretty sure that the authors put together a story that would not fit what actually happened if we could have been there to see it.

  • Oh great. (Score:2, Funny)

    by kulakovich ( 580584 )

    Now it's fish with limbs.

    Next they'll keep changing the channel and mucking with the volume.

    kulakovich
  • So the Darwin fish [evolvefish.com] on my car is anatomically correct? Cool.

  • A minor nit... (Score:2, Informative)

    by ArghBlarg ( 79067 )
    "Permanent land-living animals took another 30 million years to develop into reptiles, birds and mammals, but what happened during that transition is unclear."

    Birds didn't evolve, to our knowledge, for a LOT more than 30 million years after the Devonian. Late Cretaceous, 65 million years or so.

    (IANAPaleontologist, but I wanted to be one when I was a kid, heh)

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