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  • #16
    Originally posted by lee_merrill View Post
    Well, they say:

    Source: Science

    The arthropod Fuxianhuia from the Chengjiang fauna displays primitive aspects of cephalic segmentation and trunk limb morphology that indicate a basal position within Euarthropoda.

    Source

    © Copyright Original Source


    So yes, it does make sense to talk in such terms.
    Well, in that case, i have to apologize. The field as a whole has moved to using "basal" and "derived", which are more descriptive and scientifically accurate. But if a scientific paper is using the term, i can hardly fault you for doing so.

    Originally posted by lee_merrill View Post
    So if this was the case with arthropods, that only exacerbates the problem!
    But there is no problem!

    Look, phylogenetic groups are defined by having members all or mostly share certain features. Arthropods, for example, are defined as having multiple appendages, segmented bodies, etc. Some of these presently shared features will be present in fossil arthropods, going back to the first arthropods near the origin of the group - that's how those first arthropods are defined as arthropods, after all. A subset of them will also be present in the non-arthropod ancestors that gave rise to the arthropods.

    For those reasons, you should expect at least some of the features of modern phylogenetic groups to be present not only in their earliest members, but also in the ancestors of the earliest members.

    (There are complications like features that are present in all early and some present members, but lost in other members, but we can set that aside for now.)

    This work suggests that the structure of the insect brain may be one of those things that can be traced back to the earliest arthropods, and perhaps even to their ancestors. Given that this is precisely the behavior we'd expect in a phylogenetic group, why do you call it a problem?
    "Any sufficiently advanced stupidity is indistinguishable from trolling."

    Comment


    • #17
      Originally posted by TheLurch View Post
      This work suggests that the structure of the insect brain may be one of those things that can be traced back to the earliest arthropods, and perhaps even to their ancestors. Given that this is precisely the behavior we'd expect in a phylogenetic group, why do you call it a problem?
      Well, whence the complex brain and cardiovascular system, then? The earlier these appear, the more of a conundrum it becomes.

      Source: New Scientist

      The most specialised groups of neurons – the first brain-like structure – developed near the mouth and primitive eyes.

      Our view of this momentous event is hazy. According to many biologists, it happened in a worm-like creature known as the urbilaterian (see diagram), the ancestor of most living animals including vertebrates, molluscs and insects. Strangely, though, some of its descendants, such as the acorn worm, lack this neuronal hub.

      It is possible the urbilaterian never had a brain, and that it later evolved many times independently. Or it could be that the ancestors of the acorn worm had a primitive brain and lost it – which suggests the costs of building brains sometimes outweigh the benefits.

      Source

      © Copyright Original Source



      Blessings,
      Lee
      "What I pray of you is, to keep your eye upon Him, for that is everything. Do you say, 'How am I to keep my eye on Him?' I reply, keep your eye off everything else, and you will soon see Him. All depends on the eye of faith being kept on Him. How simple it is!" (J.B. Stoney)

      Comment


      • #18
        Originally posted by lee_merrill View Post
        Well, whence the complex brain and cardiovascular system, then? The earlier these appear, the more of a conundrum it becomes.
        Every tissue is complex. An exoskeleton is complex. A digestive system is complex. Appendages are complex. If something else had formed earlier, you'd just be complaining that that was a problem.

        Your issue appears to be the fact that complex tissues appeared at all. Is there any evidence that could convince you that otherwise?
        "Any sufficiently advanced stupidity is indistinguishable from trolling."

        Comment


        • #19
          Originally posted by TheLurch View Post
          Every tissue is complex. An exoskeleton is complex. A digestive system is complex. Appendages are complex. If something else had formed earlier, you'd just be complaining that that was a problem.
          If they formed unexpectedly early.

          Your issue appears to be the fact that complex tissues appeared at all. Is there any evidence that could convince you that otherwise?
          If the early arthropods had a basal brain, that would be more along the lines of what evolution would predict. As it is, we see a complex brain and cardiovascular system early in the Cambrian, at the base of a branch, which makes the Cambrian explosion more explosive.

          Blessings,
          Lee
          "What I pray of you is, to keep your eye upon Him, for that is everything. Do you say, 'How am I to keep my eye on Him?' I reply, keep your eye off everything else, and you will soon see Him. All depends on the eye of faith being kept on Him. How simple it is!" (J.B. Stoney)

          Comment


          • #20
            Originally posted by lee_merrill View Post
            If they formed unexpectedly early.
            So what?

            If the early arthropods had a basal brain, that would be more along the lines of what evolution would predict. As it is, we see a complex brain and cardiovascular system early in the Cambrian, at the base of a branch, which makes the Cambrian explosion more explosive.
            . . . because the evolving lineage of arthropods is older then expected. The Cambrian explosion was more explosive then previously thought, OK. Were still dealing with millions if not tens of millions or more in the evolutionary process.

            You still have not presented any significant problems with the Precambrian and Cambrian evolution simply as science develops a more complete record as more fossils are found over time to fill in the gaps as has been done in the past when new fossils are found.
            Last edited by shunyadragon; 05-14-2019, 02:53 PM.
            Glendower: I can call spirits from the vasty deep.
            Hotspur: Why, so can I, or so can any man;
            But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

            go with the flow the river knows . . .

            Frank

            I do not know, therefore everything is in pencil.

            Comment


            • #21
              Originally posted by lee_merrill View Post
              If they formed unexpectedly early.
              But at least some of them HAD to be there early, or these wouldn't be arthropods.

              Originally posted by lee_merrill View Post
              If the early arthropods had a basal brain, that would be more along the lines of what evolution would predict. As it is, we see a complex brain and cardiovascular system early in the Cambrian, at the base of a branch, which makes the Cambrian explosion more explosive.
              No, and no. The fact that this brain structure was present in the early arthropods show that it WAS basal. By definition. And again, you're demanding that early arthropods not have any of the properties that make them arthropods, yet still somehow be arthropods.


              Let me back up and ask you a question: do you know enough neuroanatomy to understand what makes the structure seen in the earliest arthropods "complex"? Can you identify a similar yet less complex structure in non-arthropods?

              If both answers are no, why do you think you can draw any conclusions about this topic?
              "Any sufficiently advanced stupidity is indistinguishable from trolling."

              Comment


              • #22
                Originally posted by TheLurch View Post
                The fact that this brain structure was present in the early arthropods show that it WAS basal. By definition.
                Sorry, I should have said "simple" instead of "basal".

                Let me back up and ask you a question: do you know enough neuroanatomy to understand what makes the structure seen in the earliest arthropods "complex"? Can you identify a similar yet less complex structure in non-arthropods?

                If both answers are no, why do you think you can draw any conclusions about this topic?
                I can't, but Ma et. al. can:

                Source: Nature

                Resolving arguments about whether the simple brain of a branchiopod approximates an ancestral insect brain or whether it is the result of secondary simplification has until now been hindered by lack of fossil evidence. The complex brain of Fuxianhuia accords with cladistic analyses on the basis of neural characters, suggesting that Branchiopoda derive from a malacostracan-like ancestor but underwent evolutionary reduction and character reversal of brain centres that are common to hexapods and malacostracans. The early origin of sophisticated brains provides a probable driver for versatile visual behaviours, a view that accords with compound eyes from the early Cambrian that were, in size and resolution, equal to those of modern insects and malacostracans.

                Source

                © Copyright Original Source


                Emphasis mine...

                Blessings,
                Lee
                "What I pray of you is, to keep your eye upon Him, for that is everything. Do you say, 'How am I to keep my eye on Him?' I reply, keep your eye off everything else, and you will soon see Him. All depends on the eye of faith being kept on Him. How simple it is!" (J.B. Stoney)

                Comment


                • #23
                  Originally posted by lee_merrill View Post
                  Sorry, I should have said "simple" instead of "basal".


                  I can't, but Ma et. al. can:

                  Source: Nature

                  Resolving arguments about whether the simple brain of a branchiopod approximates an ancestral insect brain or whether it is the result of secondary simplification has until now been hindered by lack of fossil evidence. The complex brain of Fuxianhuia accords with cladistic analyses on the basis of neural characters, suggesting that Branchiopoda derive from a malacostracan-like ancestor but underwent evolutionary reduction and character reversal of brain centres that are common to hexapods and malacostracans. The early origin of sophisticated brains provides a probable driver for versatile visual behaviours, a view that accords with compound eyes from the early Cambrian that were, in size and resolution, equal to those of modern insects and malacostracans.

                  Source

                  © Copyright Original Source


                  Emphasis mine...

                  Blessings,
                  Lee
                  OK,but so what? You offer nothing in terms of significant objections to the evidence of evolution other than selectively bold references to justify to mystically justify your agenda. Please provide a coherent argument other than 'arguing from ignorance.'

                  Yes, there is an earlier that previously known origin of a sophisticated brain, so what?!?!?!
                  Last edited by shunyadragon; 05-14-2019, 10:44 PM.
                  Glendower: I can call spirits from the vasty deep.
                  Hotspur: Why, so can I, or so can any man;
                  But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

                  go with the flow the river knows . . .

                  Frank

                  I do not know, therefore everything is in pencil.

                  Comment


                  • #24
                    Lee, why don't you accept Common Descent, if even Behe accepts it? What makes you think your view is superior?

                    Regards.

                    Comment


                    • #25
                      Originally posted by lee_merrill View Post
                      I can't, but Ma et. al. can:

                      Source: Nature

                      Resolving arguments about whether the simple brain of a branchiopod approximates an ancestral insect brain or whether it is the result of secondary simplification has until now been hindered by lack of fossil evidence. The complex brain of Fuxianhuia accords with cladistic analyses on the basis of neural characters, suggesting that Branchiopoda derive from a malacostracan-like ancestor but underwent evolutionary reduction and character reversal of brain centres that are common to hexapods and malacostracans. The early origin of sophisticated brains provides a probable driver for versatile visual behaviours, a view that accords with compound eyes from the early Cambrian that were, in size and resolution, equal to those of modern insects and malacostracans.

                      Source

                      © Copyright Original Source


                      Emphasis mine...
                      So, basically, you think you can add bold around words you like in a body of text you don't understand, and that makes an argument?

                      The quoted section does not support you in any way. Basically, there are a group of arthropods (branchiopods) that do not share the brain structure that insects have. The question was then which of these two states was ancestral, the insect or the branchiopod one? It could be that insects came later, and elaborated an apparently simple branchiopod setup, or that branchiopods evolved a stripped down brain structure even as everything else in arthropoda kept a more insect-like setup.

                      The fossil answers this as the insect one being ancestral.

                      What should you take home from this? The fact that evolutionary biologists had already considered the insect-like structure being the ancestral state as a possibility that was a) completely realistic; and b) perfectly consistent with evolution. Thus, calling the discovery that it was ancestral should not only have been unsurprising, it should have been described as supporting a pre-existing contention.

                      Newsflash: don't confuse a few quotes that make for good press with the actual state of scientific knowledge.
                      "Any sufficiently advanced stupidity is indistinguishable from trolling."

                      Comment


                      • #26
                        Originally posted by shunyadragon View Post
                        Yes, there is an earlier that previously known origin of a sophisticated brain, so what?!?!?!
                        So a sophisticated brain this early in the Cambrian is surprising, especially at the base of a branch. This pushes back the evolution of the brain and cardiovascular system into the Precambrian or even the Ediacaran, which is problematic.

                        Blessings,
                        Lee
                        "What I pray of you is, to keep your eye upon Him, for that is everything. Do you say, 'How am I to keep my eye on Him?' I reply, keep your eye off everything else, and you will soon see Him. All depends on the eye of faith being kept on Him. How simple it is!" (J.B. Stoney)

                        Comment


                        • #27
                          Originally posted by Seeker View Post
                          Lee, why don't you accept Common Descent, if even Behe accepts it? What makes you think your view is superior?
                          Because of radiation events such as the Cambrian explosion (re Darwin's Doubt and Debating Darwin's Doubt), and the theological difficulties with there being no historical Adam and Eve. Not to mention mitochondrial Eve...

                          Blessings,
                          Lee
                          "What I pray of you is, to keep your eye upon Him, for that is everything. Do you say, 'How am I to keep my eye on Him?' I reply, keep your eye off everything else, and you will soon see Him. All depends on the eye of faith being kept on Him. How simple it is!" (J.B. Stoney)

                          Comment


                          • #28
                            Originally posted by TheLurch View Post
                            So, basically, you think you can add bold around words you like in a body of text you don't understand, and that makes an argument?
                            No, you were challenging me on simple and complex neuroanatomy, and this paper deals with that.

                            Blessings,
                            Lee
                            "What I pray of you is, to keep your eye upon Him, for that is everything. Do you say, 'How am I to keep my eye on Him?' I reply, keep your eye off everything else, and you will soon see Him. All depends on the eye of faith being kept on Him. How simple it is!" (J.B. Stoney)

                            Comment


                            • #29
                              Originally posted by lee_merrill View Post
                              So a sophisticated brain this early in the Cambrian is surprising, especially at the base of a branch. This pushes back the evolution of the brain and cardiovascular system into the Precambrian or even the Ediacaran, which is problematic.

                              Blessings,
                              Lee
                              No, no problem it just changes the time frame more likely earlier in the Cambrian, ie the Ediacaran than the preCambrian. There are tens of millions if not more for evolution between the more primitive known fossils and the Fuxianhuia. There is nothing problematic for pushing back the timing of the evolution of Fuxianhuia. I believe TheLurch has patiently explained the proper view of the science concerning the nature of the finds of Fuxianhuia. Your argument remains an unethical 'argument from ignorance' to justify your agenda, and not to understand the science of evolution. Your following response more than reveals your agenda, and it is not science.

                              Because of radiation events such as the Cambrian explosion (re Darwin's Doubt and Debating Darwin's Doubt), and the theological difficulties with there being no historical Adam and Eve. Not to mention mitochondrial Eve...
                              The books you refer to are not scientific references of merit.
                              Glendower: I can call spirits from the vasty deep.
                              Hotspur: Why, so can I, or so can any man;
                              But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

                              go with the flow the river knows . . .

                              Frank

                              I do not know, therefore everything is in pencil.

                              Comment


                              • #30
                                Originally posted by lee_merrill View Post
                                So a sophisticated brain this early in the Cambrian is surprising, especially at the base of a branch. This pushes back the evolution of the brain and cardiovascular system into the Precambrian or even the Ediacaran, which is problematic.
                                Why? These systems had to originate at some point.
                                "Any sufficiently advanced stupidity is indistinguishable from trolling."

                                Comment

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