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Fossil discovery helps bridge gap between Ediacaran animals & those from the Cambrian

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  • #31
    Thank you for your reply to my point.

    Originally posted by TheLurch View Post
    We know that the fossils we see represent only a fraction of the total diversity of life. So, having a few examples of pre-Cambrian bilaterians indicates that there was a larger diversity prior to the explosion, and thus less total diversification to explain.
    I might just as well argue that the Cambrian explosion was more complex due to animals we have not yet found. But it seems best to stick with what we have, and to make any conclusions based on that. I would add that Namacalathus hermanastes is debatable, as demonstrated by its being debated here and elsewhere.

    It also extends the time available for that diversification.
    Which is why I posted a quote by Meyers saying that the timeframe can be extended by 10 million years or so, and still the conundrum remains.

    And, by identifying a common ancestor for different groups, we can better recognize which changes were actually required, and which novel features predated the explosion.
    Fair enough...

    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


    • #32
      Originally posted by rogue06 View Post
      It is rather frustrating that after decades of proponents of I.D. and creationists (Cdesign Proponentsists ) harping about there being no ancestors for Cambrian life forms (Lee's buddy Stephen Meyer devoted something like two chapters in his book Darwin's Doubt prattling on about it and the Discovery Institute produced an entire movie Darwin’s Dilemma dedicated to espousing this assertion), but now Lee seeks to dissimulate the notion that finding an example of just such a precursor is no big deal and quickly wants to shift the issue to something else and act like that's what it was all along (move the goal posts).
      And I am explaining why it's not that important, the Cambrian diversification still needs to be explained, and moving the boundary back (or forward) does not substantially explain this.

      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


      • #33
        Originally posted by lee_merrill View Post
        And I am explaining why it's not that important, the Cambrian diversification still needs to be explained, and moving the boundary back (or forward) does not substantially explain this.

        Blessings,
        Lee
        The "H" in Intelligent Design advocate stands for honesty

        I'm always still in trouble again

        "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
        "Of course, human life begins at fertilization that’s not the argument." --Tassman

        Comment


        • #34
          Originally posted by lee_merrill View Post
          I might just as well argue that the Cambrian explosion was more complex due to animals we have not yet found. But it seems best to stick with what we have, and to make any conclusions based on that.
          Except we already have large beds of fossils representing entire ecosystems for the Cambrian. I don't believe we have the equivalent from the Ediacaran, though it's not an area i know as well as many others.

          Originally posted by lee_merrill View Post
          I would add that Namacalathus hermanastes is debatable, as demonstrated by its being debated here and elsewhere.
          No, that's not the way things work. If i start a pointless argument about the moon being made of cheese here, it doesn't make the composition of the moon "debatable."

          Originally posted by lee_merrill View Post
          Which is why I posted a quote by Meyers saying that the timeframe can be extended by 10 million years or so, and still the conundrum remains.
          Quoting Meyers in a discussion of evolution is like quoting Julia Childs in a discussion of quantum mechanics. Although, unlike Meyer and to her credit, Childs never claimed to have expertise she lacked.

          In any case, this seems to be the argument:
          Originally posted by lee_merrill View Post
          And I am explaining why it's not that important, the Cambrian diversification still needs to be explained, and moving the boundary back (or forward) does not substantially explain this.
          Does the diversification of mammals after the extinction of dinosaurs need an explanation? The loss of dinosaurs opened up a huge number of ecological niches that mammals diversified into. It's pretty basic ecology, and considered a reasonable explanation by everyone. The only debates are about the timing and details.

          It's clear there was a mass extinctions to end the Ediacaran - almost all the metazoan species that were common during the Ediacaran did not survive to the Cambrian, and a series of global glaciations seem to provide all the cause we could ask for regarding a cause. Post-glaciations, a different group of metazoans diversified into the now-open ecology. It's almost an exact parallel to the post-K/T diversification of mammals.

          The "almost" part simply comes from the fact that, prior to the end-Ediacaran extinction, most of the ecological niches were unoccupied, since metazoans were just getting started.


          It's so completely obvious that it's utterly bewildering to see you saying that we need some sort of explanation. It's like watching someone standing in a tree-filled yard in October, demanding an explanation for all the leaves on the ground.

          "Any sufficiently advanced stupidity is indistinguishable from trolling."

          Comment


          • #35
            Originally posted by TheLurch View Post
            Except we already have large beds of fossils representing entire ecosystems for the Cambrian. I don't believe we have the equivalent from the Ediacaran, though it's not an area i know as well as many others.


            No, that's not the way things work. If i start a pointless argument about the moon being made of cheese here, it doesn't make the composition of the moon "debatable."


            Quoting Meyers in a discussion of evolution is like quoting Julia Childs in a discussion of quantum mechanics. Although, unlike Meyer and to her credit, Childs never claimed to have expertise she lacked.

            In any case, this seems to be the argument:

            Does the diversification of mammals after the extinction of dinosaurs need an explanation? The loss of dinosaurs opened up a huge number of ecological niches that mammals diversified into. It's pretty basic ecology, and considered a reasonable explanation by everyone. The only debates are about the timing and details.

            It's clear there was a mass extinctions to end the Ediacaran - almost all the metazoan species that were common during the Ediacaran did not survive to the Cambrian, and a series of global glaciations seem to provide all the cause we could ask for regarding a cause. Post-glaciations, a different group of metazoans diversified into the now-open ecology. It's almost an exact parallel to the post-K/T diversification of mammals.

            The "almost" part simply comes from the fact that, prior to the end-Ediacaran extinction, most of the ecological niches were unoccupied, since metazoans were just getting started.


            It's so completely obvious that it's utterly bewildering to see you saying that we need some sort of explanation. It's like watching someone standing in a tree-filled yard in October, demanding an explanation for all the leaves on the ground.
            There have been actually been several rapid diversifications of life during earth's history apparently including one at least roughly 33 million years before to the "Cambrian explosion" (the "Avalon explosion" of the Ediacaran biota in the pre-Cambrian). The Cambrian "Explosion" is just one more meaning that there really is nothing unique about adaptive radiations like that.

            For instance, there was the Ordovician radiation or biodiversity event, some times called the great Ordovician biodiversification event (GOBE) which is considered one of the most extensive diversifications of life seen and followed the mass extinction event that marks the Cambrian-Ordovician boundary. It saw the diversification of trilobites, echinoderms, brachiopods, gastropods and bivalves as well as the rise of true corals, among other things. In fact while the evolutionary radiation during the Cambrian gave rise to most of the modern phyla, GOBE is thought to have been responsible for "filling out" these phyla with the modern -- as well as numerous extinct -- classes and lower-level taxa increasing global diversity several fold.

            There was a Devonian radiation, which saw another re-radiation of trilobite species, as well as the rise and diversification of large predatory fish such as sharks, ray-finned fish, lobe-finned fish, placoderms, and acanthodians. The Devonian period also experienced a one-time explosion in the evolution of terrestrial plants: after a cryptic history beginning about 450 mya, land plants underwent a uniquely rapid adaptive radiation. And speaking of terrestrial plants 100 mya (mid Cretaceous) witnessed a rapid radiation of angiosperms (flowering plants) as they diversified. It was also the beginning of an enormous diversification of insects -- a radiation that has continued almost unchecked since then.

            At the end of the Permian, when an estimated 90% of species and 50-60% of families appear to have become extinct and were replaced by a small number of genera which rapidly diversified to fill a wide number of ecological niches during the early Triassic. For instance Lystrosaurus, a small dicynodont therapsid, were by far the most common terrestrial vertebrates for millions of years and appear to have accounted for roughly 90% or more of early Triassic terrestrial vertebrates. The Triassic was also the period when the aforementioned continuing diversification of insects probably was at its peak and the radiation of organisms in both marine and terrestrial ecosystems marked the first major step in the origin of modern ecosystems, which is why this time has been called the "Dawn of the Modern World."

            And the most recent was the one taking place at the start of the Cenozoic and generally referred to as the Mesozoic-Cenozoic radiation and was possibly the largest of these events. There is, after all, a reason that this era is called the Cenozoic which means "New Life." It affected both terrestrial and marine flora and fauna resulting in "modern" marine fauna replacing much of the Paleozoic fauna (the replacement of brachiopod-dominated environment with one dominated by mollusks) and of course the rapid radiation of mammals after the Cretaceous.

            The ONLY reason creationists and Intelligent Design advocates focused on the Cambrian was because they continued to insist that the life forms that diversified during it had no predecessors. That they, as Weiland declared "appear[ed] in the Cambrian with no evolutionary ancestors."

            But now we can show without a doubt that this claim is false.
            Last edited by rogue06; 01-16-2021, 07:43 PM.

            I'm always still in trouble again

            "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
            "Of course, human life begins at fertilization that’s not the argument." --Tassman

            Comment


            • #36
              Originally posted by TheLurch View Post
              Post-glaciations, a different group of metazoans diversified into the now-open ecology. It's almost an exact parallel to the post-K/T diversification of mammals.
              But open niches does nothing to explain the appearance of new body plans in the Cambrian explosion.

              Source: Darwin's Doubt

              Discoveries at Chengjiang contradict the bottom-up pattern that neo-Darwinism expects. The site does not show the gradual emergence of unique species followed slowly but surely by the emergence of representatives of ever higher and more disparate taxa, leading to novel phyla. Instead, like the Burgess Shale, it shows body plan–level disparity arising first and suddenly, with no evidence of a gradual unfolding and ranging through the lower taxonomic groups.

              © 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


              • #37
                Originally posted by rogue06 View Post
                The ONLY reason creationists and Intelligent Design advocates focused on the Cambrian was because they continued to insist that the life forms that diversified during it had no predecessors. That they, as Weiland declared "appear[ed] in the Cambrian with no evolutionary ancestors."
                And moving the boundary of diversification back by a few animals does little to explain the arrival of all the new body plans.

                Source: Darwin's Doubt

                Even the most favorable interpretations of these trace fossils suggest that they indicate the presence of no more than two animal body plans (of largely unknown characteristics). Thus, the Ediacaran record falls far short of establishing the existence of the wide variety of transitional intermediates that a Darwinian view of life’s history requires. The Cambrian explosion attests to the first appearance of organisms representing at least twenty phyla and many more subphyla and classes, each manifesting distinctive body plans. In a best case, the Ediacaran forms represent possible ancestors for, at most, four distinct Cambrian body plans, even counting those documented only by trace fossils. This leaves the vast majority of the Cambrian phyla with no apparent ancestors in the Precambrian rocks...

                © 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


                • #38
                  Originally posted by lee_merrill View Post
                  But open niches does nothing to explain the appearance of new body plans in the Cambrian explosion.
                  Why doesn't it? If there are open niches that no previously existing body plan can exploit, why wouldn't a new one figure out how to exploit it?

                  You're mistaking an evidence-free assertion for an argument.

                  And, coincidentally and on the topic of this thread, the more bilaterians we discover in the Ediacaran, the fewer body plans that actually arose in the Cambrian. Which is precisely the thing you said wasn't important just a page or two ago, back when you wanted to dismiss the significance of this find. In other words, you dismissed a finding's implications as unimportant, only to turn around and say it's a problem that we don't have evidence of what you just said was unimportant.

                  I'd consider it highly dishonest if it weren't for the fact that you seem to be pathologically incapable of remembering what you wrote two days ago.


                  For those whose feet are more firmly planted in the real world, i'd note the the implications of Precambrian bilaterians is more important in this regard than it might appear. We tend to find that organism's like this have features that show up in diverse groups of organisms in the ensuing period, much like early mammals have features that are now present in everything from whales to bats. So, a single example early on often represents an ancestral form of many different branches in the evolutionary tree a few million years later.

                  I'd also like to point out that "body plan" is a vague term, and if it's being used for this type of argument, it really needs to be made well defined and quantitative.
                  "Any sufficiently advanced stupidity is indistinguishable from trolling."

                  Comment


                  • #39
                    Originally posted by lee_merrill View Post
                    And moving the boundary of diversification back by a few animals does little to explain the arrival of all the new body plans.

                    Source: Darwin's Doubt

                    Even the most favorable interpretations of these trace fossils suggest that they indicate the presence of no more than two animal body plans (of largely unknown characteristics). Thus, the Ediacaran record falls far short of establishing the existence of the wide variety of transitional intermediates that a Darwinian view of life’s history requires. The Cambrian explosion attests to the first appearance of organisms representing at least twenty phyla and many more subphyla and classes, each manifesting distinctive body plans. In a best case, the Ediacaran forms represent possible ancestors for, at most, four distinct Cambrian body plans, even counting those documented only by trace fossils. This leaves the vast majority of the Cambrian phyla with no apparent ancestors in the Precambrian rocks...

                    © Copyright Original Source



                    Blessings,
                    Lee
                    I am certain that all the basic body plans were found in the Ediacarian, but of course in simpler forms.

                    You are still citing phony non-science references with a religious agenda. I will cite 2020 scientific reference.

                    Source: https://dev.biologists.org/content/147/4/dev182899



                    The origin of animal body plans: a view from fossil evidence and the regulatory genome

                    Douglas H. Erwin
                    Development 2020 147: dev182899 doi: 10.1242/dev.182899 Published 20 February 2020

                    Introduction


                    The discovery of deep homologies (see Glossary, Box 1) across bilaterian animals, and highly conserved, developmentally significant genes among cnidarians, sponges and the closest relatives of Metazoa, has revealed a new understanding about the early history of animals (Fig. 1). In the 1990s, the discovery of extensive conservation of developmental genes between vertebrates and arthropods, such as the Hox genes Pax6 and distalless, led to ongoing disputes regarding the morphology of the last common ancestor of these two clades (the protostome-deuterostome ancestor or PDA): a morphologically complex urbilaterian, based on assumptions that genetic homology implies conservation of developmental processes (e.g. Arendt, 2008; Carroll et al., 2001; De Robertis and Sasai, 1996; De Robertis, 2008; Knoll and Carroll, 1999; Panganiban et al., 1997), versus a morphologically simpler ancestral urbilaterian (Valentine et al., 1999; Davidson and Erwin, 2006; Erwin and Davidson, 2002; Genikhovich and Technau, 2017; Hejnol and Martindale, 2008; Tweedt and Erwin, 2015).

                    Fossil evidence for the early history of animals

                    When Charles Darwin wrote The Origin of Species he was troubled by the sudden appearance of animal fossils. Since the 1980s, extensive field studies, the discovery of new fossil clades, an increasingly resolved temporal framework and detailed phylogenetic studies have revealed the appearance and early diversification of metazoan clades in exquisite detail from the mid-Ediacaran (∼570 Ma; Fig. 3) to the early stages of the Cambrian Period (∼539 Ma). The fossil record preserves three different types of information about the early history of animals (Fig. 4). Body fossils generally receive the most attention; however, important information also comes from burrows and trackways (trace fossils), and organic from materials (such as lipid biomarkers).

                    Discussion


                    This comparative approach reveals several general patterns in the evolution of the metazoan regulatory genome. First, much of the ‘metazoan developmental toolkit’ appeared almost a billion years ago with the origin and early evolution of Holozoa – particularly the combinatoric TF-TF interactions and proximal regulation – to allow a complex life cycle with multiple cell types. Second, comparative studies of other holozoan clades has shown that the extent of the regulatory genome of the last common metazoan ancestor – including distal enhancers, the number of cell types and morphological complexity – was far greater than appreciated even one decade ago, lending increasing credence to some variant of the temporal-to-spatial transition model. Third, I have argued here that the PDA was less complex than has been argued in the past, which necessarily implies that extensive co-option of regulatory modules must have occurred independently in bilaterian clades. Finally, the origin of Bilateria has been identified as a particularly critical node in the evolution of the regulatory genome. Distal enhancers became far more prominent, CTCF sequences and TADs provided a new level of transcriptional control, and GRN hierarchies expanded through intercalation, co-option and other processes. Integrating our knowledge of the evolution of developmental patterns and processes with insights from molecular clock estimates and from the fossil record reveals the extent of co-option of regulatory components into new functions, particularly across the bilaterians. Together, this information provides a much richer view of evolutionary dynamics during one of the most crucial episodes in the history of life.

                    Here, I have focused on the origins of particular regulatory novelties which have expanded the capacity of the regulatory genome. Beyond these, however, a number of trends and recurrent patterns appear to be similar across animal clades. At the level of genome structure, major lineages show distinct patterns of gene gain and loss (with the suite of regulatory genes in cnidarians more similar to those of deuterostomes than to protostomes). There have been increases in gene clustering, macro- and micro-synteny (see Glossary, Box 1) and intron density, which may have facilitated the extensive expansion of most families of metazoan transcription factors (Irimia et al., 2012; Zimmermann et al., 2019). The complexity of GRNs has increased during the past 600 Ma through an increase in promoters and transcription start sites and the increasing hierarchical structuring of GRNs as subcircuits have been co-opted for new functions (Sabarís et al., 2019).
                    Conclusions and future directions


                    New comparative studies of animals and extant holozoans will continue to expand our understanding of regulatory evolution in early animals. Of particular interest will be comparative studies of GRNs involved in cell-type differentiation in different clades, and in regulatory control of regional patterning. Single-cell transcriptomics and related studies have revolutionized the understanding of cell type evolution (Achim and Arendt, 2014; Arendt, 2008; Arendt et al., 2016a; Sebé-Pedrós et al., 2018a) and provide a foundation for detailed comparative studies of GRNs. Despite the advances discussed in this Review, many unresolved questions remain: how have spatial and temporal regulators been intercalated to construct more hierarchical GRNs, which can then be co-opted for new developmental functions? Did hierarchically structured GRNs arise before the PDA? Or during the early divergence of deuterostomes, for example, but before the origin of echinoderms and chordates? Comparative studies will also reveal whether some components of GRNs are more refractory to evolutionary change than others. Another issue for future study is whether the nature of regulatory changes has itself evolved over time. The account here provides tentative support for this suggestion, with the generation of regulatory novelties associated with holozoans and early in animal evolution (Erwin, 2015; Simakov and Kawashima, 2017), with later evolutionary events dominated by co-option and repatterning of GRNs.

                    © Copyright Original Source



                    Please start citing up to date scientific journals, and stop making a fool of your self with non-scientific Creationist references.


                    Last edited by shunyadragon; 01-18-2021, 12:29 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


                    • #40
                      Originally posted by lee_merrill View Post
                      If a lack of pre-Cambrian precursors to Cambrian life was not very significant, why was it mentioned so often?
                      In order to emphasize the significance of the diversification, I would guess.
                      It doesn't. The two are independent.

                      Maybe you should stop guessing and try research or logic instead.
                      Jorge: Functional Complex Information is INFORMATION that is complex and functional.

                      mikewhitney: What if the speed of light changed when light is passing through water? ... I have 3 semesters of college Physics.

                      Mountain Man: First of all, the Bible is a fixed document.
                      Mountain Man: … this is how liberals argue these days, with labels instead of ideas.

                      Comment


                      • #41
                        Originally posted by lee_merrill View Post
                        I would add that Namacalathus hermanastes is debatable, as demonstrated by its being debated here and elsewhere.
                        Being "debatable" requires actual debate, not just sniping by incompetent idiots.

                        Jorge: Functional Complex Information is INFORMATION that is complex and functional.

                        mikewhitney: What if the speed of light changed when light is passing through water? ... I have 3 semesters of college Physics.

                        Mountain Man: First of all, the Bible is a fixed document.
                        Mountain Man: … this is how liberals argue these days, with labels instead of ideas.

                        Comment


                        • #42
                          Originally posted by rogue06 View Post
                          The "H" in Intelligent Design advocate stands for honesty
                          I'm borrowing this.

                          Jorge: Functional Complex Information is INFORMATION that is complex and functional.

                          mikewhitney: What if the speed of light changed when light is passing through water? ... I have 3 semesters of college Physics.

                          Mountain Man: First of all, the Bible is a fixed document.
                          Mountain Man: … this is how liberals argue these days, with labels instead of ideas.

                          Comment


                          • #43
                            Originally posted by Roy View Post
                            It doesn't. The two are independent.

                            Maybe you should stop guessing and try research or logic instead.
                            Or bother to get at least some grounding in things like basic biology so he'd at least have a clue what is being discussed.

                            I'm always still in trouble again

                            "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
                            "Of course, human life begins at fertilization that’s not the argument." --Tassman

                            Comment


                            • #44
                              Originally posted by TheLurch View Post
                              Why doesn't it? If there are open niches that no previously existing body plan can exploit, why wouldn't a new one figure out how to exploit it?
                              Because the edge of evolution, Behe places at two new protein-protein interactions.

                              And, coincidentally and on the topic of this thread, the more bilaterians we discover in the Ediacaran, the fewer body plans that actually arose in the Cambrian. Which is precisely the thing you said wasn't important just a page or two ago, back when you wanted to dismiss the significance of this find. In other words, you dismissed a finding's implications as unimportant, only to turn around and say it's a problem that we don't have evidence of what you just said was unimportant.
                              No, you misunderstand me, I mean that the important point is that we don't see a Darwinian diversification of animals in the Cambrian and pre-Cambrian. Moving the boundary around does not explain this.

                              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


                              • #45
                                Originally posted by shunyadragon View Post
                                Source: dev.biologists.org

                                The origins and the early evolution of multicellular animals required the exploitation of holozoan genomic regulatory elements and the acquisition of new regulatory tools. Comparative studies of metazoans and their relatives now allow reconstruction of the evolution of the metazoan regulatory genome...

                                © Copyright Original Source

                                There's a problem here, though, and that's that reconstruction of evolution by comparative studies does not demonstrate how the putative changes took place.

                                Source: dev.biologists.org

                                The complexity of GRNs has increased during the past 600 Ma through an increase in promoters and transcription start sites and the increasing hierarchical structuring of GRNs as subcircuits have been co-opted for new functions (Sabarís et al., 2019).

                                © Copyright Original Source


                                I respond with this excerpt from Darwin's Doubt:

                                Source: Darwin's Doubt

                                mutations that are expressed early in the development of animals have probably the only realistic chance of producing large-scale macroevolutionary change. As evolutionary geneticists Bernard John and George Miklos explain, “macroevolutionary change” requires changes in “very early embryogenesis.” Former Yale University evolutionary biologist Keith Thomson concurs: only mutations expressed early in the development of organisms can produce large-scale macroevolutionary change.

                                Yet from the first experiments by geneticist T. H. Morgan systematically mutating fruit flies early in the twentieth century until today, as many model species have been subjected to mutagenesis, developmental biology has shown that mutations affecting body-plan formation expressed early in development inevitably damage the organism. ... As one of the founders of neo-Darwinism geneticist R. A. Fisher noted, such mutations are “either definitely pathological (most often lethal) in their effects,” or they result in an organism that cannot survive “in the wild state.”11

                                11. Fisher, The Genetical Theory of Natural Selection, 44.

                                © Copyright Original Source


                                So changes to regulatory DNA would have to affect early development, yet such mutations seem to be invariably pathological or fatal.

                                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

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