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Panderichthys—A Fish with Fingers?

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Panderichthys—A Fish with Fingers? Perspectives Hazen and his team avoid taking taxa, not by merging two or more Panderichthys—a the evolutionary analogy further, taxa into one. By leaving things at although the ingredients are there! the shallowest level possible, Hazen fish with fingers? When claiming mineral species do not & Co. hope to blaze the trail toward change over time, he is only telling integration into either ‘geobiology’ or Shaun Doyle half of the story. There are minerals ‘biogeology’! known as structural polymorphs, an Is this a new challenge to nce more, fish-to-tetrapod example of which is the andalusite- 1–2 silimanite series.8 Although there young-earth creation models? Oevolution is paraded around, are several different minerals in this this time with a study suggesting Not really. If there is a challenge, the replacement of Tiktaalik, the series, they are all formed from the it’s mostly a methodological one. icon of fish–tetrapod evolution, with same three chemical elements: Al, ‘Integration’ seems to be the battle cry of Si and O in the empirical formula the evolutionary establishment but the the 90–130-cm-long Panderichthys rhombolepis. However, Panderichthys Al2SiO5. Temperature and pressure shallowness of this new idea provides control the structural layout of these excellent grounds for creationists to isn’t exactly new; it was actually chemical elements thus determining dismantle it and by consequence further named in 1941.3 And it’s supposedly the mineral species: distene or kyanite expose the fallacies of Darwinian older too: 385 million years (Ma) old ( Al2[SiO4]O ), andalusite (Al2[SiO4]O) evolution. As for the deeper meaning in comparison to Tiktaalik, which is and sillimanite (Al[AlSiO5] (figure 1). of all this, we have yet another proof supposedly 380 Ma old. However, This should have been proudly added of God’s integrated creation, all parts a recent study has suggested that by Hazen to his evolutionary analogies of it working together, from minerals Panderichthys’ fin may be closer as a case of homology. to humans: ‘For the invisible things to tetrapods in morphology than Hazen is actually wrong when of Him from the creation of the world Tiktaalik,4 although evolutionary affirming that mineral species don’t are clearly seen, being understood theory would predict that tetrapod change: minerals actually do change by the things that are made…’ over time if they are exposed to (Romans 1:20). characteristics would be more recent. different physical and chemical conditions. Muscovite—a mica— References Fishing for fingers ( K2Al4[Al2Si6](OH, F)4 ) in the 1. Hazen, R.M. et al., Mineral evolution, Boisvert et al. have based their presence of CO2-rich water loses K American Mineralogist 93(11–12):1693–1720, analysis on the pectoral fin of one and F and transforms into kaolinite 2008. particular Panderichthys fossil, which ( Al [SiO ](OH) ). Darwin initially 2. Hazen, R., Mineral evolution, Carnegie 4 10 8 they reconstructed from a CT scan called this idea ‘transformism’. But Institute for Science, Geophysical laboratory, study of the fossil, which they then by adding oxygen to an existing November 2008, <videos.ciw.edu/achilles_ movies_download/mineral_evolution.mov>. mineral and forming a new mineral, used to reconstruct a 3D image of the what actually changes? One mineral 3. Mineral kingdom has co-evolved with life, fossil fin. Panderichthys was found scientists find, Science News, <www.sciencedaily. to have multiple ‘digits’ at the end into another! In a process known com/releases/2008/11/081113181035.htm>, 1 as ‘dolomitization’, the addition of September 2009. of the bony part of the pectoral fin similar to Tiktaalik’s, which Boisvert magnesium to calcite (CaCO3) changes 4. Clay material may have acted as ‘primordial et al. made out to be homologous with it into dolomite ( CaMg(CO3)2 ). womb’ for first organic molecules, According to Hazen’s evolutionary Science News, <www.sciencedaily.com/ digits on tetrapod limbs (figure 1). analogy, this should be defined as releases/2005/11/051112125422.htm>, 1 5 September 2009. Aside from the general biological and mineral evolution by mutation; it theological6 problems with excluding 5. Hansma, H.G., Granny says life evolved also exhibits natural selection since between the mica sheets, Live Science, <www. common design, Panderichthys is still the minerals have ‘adapted’ to new livescience.com/strangenews/080314-bts- unequivocally a fish with fins. chemical conditions! hansma.html>, 1 September 2009. The small distal bones found How could Hazen miss this? 6. Goldblatt, C., Lenton, T.M. and Watson, between Panderichthys and Tiktaalik Maybe he didn’t and just skillfully A.J., Bistability of atmospheric oxygen and are nothing in comparison to the avoided taking the analogy too far for the Great Oxidation, Nature 443(7112):683– 686,12 Oct. 2006. changes that need to be made between it should be obvious that this is not what Darwin meant by ‘evolution’! 7. Tapp, B., Origin of oxygen more complex than either of them and a limb, as one of imagined, Journal of Creation 21(2):3, 2007, the co-authors of the Nature paper, Per Darwinian evolution proceeds by <creation.com/content/view/6173>. mutations from within and not by Ahlberg, has admitted before: 8. Hirsch, D., Teaching phase equilibria: ‘Although these small distal bones adding pre-existing information from different kinds of reactions, <serc.carleton.edu/ outside! Darwin’s diversification research_education/equilibria/reactioncurves. bear some resemblance to tetrapod of taxa is explained by the repeated html>, 1 September 2009. digits in terms of their function splitting of one taxon into two or more and range of movement, they JOURNAL OF CREATION 23(1) 2009 11 Perspectives same bones in comparable proportions. than Tiktaalik. At any rate, it The problem is that neither of them are demonstrates that the fish–tetrapod anything like a tetrapod limb because transition was accompanied by the wrist morphology is all wrong.8 significant character incongruence As Luskin points out, there are a in functionally important number of things that need to radically structures.’4 change from Tiktaalik to get a proper However, there are no lin- tetrapod wrist/hand: eages—merely the comparing of 1. ‘Shrink Tiktaalik’s [and Pan- finished products to come up with the derichthys’] radius and reposition illusion of a lineage. it so that it articulates other bones They don’t know which of their further down the limb. smorgasboard of just-so evolutionary 2. ‘Evolve a radiale [a third bone ‘explanations’ they should use, so they alongside the ulnare and inter- leave the reader with a few possible medium that articulates with the ones to give the illusion that evolution radius]. has it all worked out, even if we don’t. 3. ‘Dramatically repattern, reposition, However, there are no lineages— and transform the existing radials merely the comparing of finished by lining them up, separating them products to come up with the illusion out to form digits. of a lineage. The story as Daeschler et 4. ‘Evolve metacarpals and phalanges al. described it remains true: so that there are real digits extending ‘Major elements of the tetrapod distally from the radius. body plan originated as a succession 5. ‘Evolve the “lotsa blobs”, i.e. of intermediate morphologies that evolve other carpal bones between evolved mosaically and in parallel the radius, ulna, and the now- among sarcopterygians closely ., ref. 3, p. 1. aligned digits to form a real wrist. related to tetrapods, allowing them et al In other words, evolve the bulk of to exploit diverse habitats in the the wrist-bones.’8 Devonian [emphases added]’.12 Another important con- The problem of mosaic and sideration is function. Since these parallel evolution is that they occur Image by Boisvert particular fins have never been seen to parts of organisms rather than the Figure 1. CT scans of Panderichthys’ in live operation, there is no reason to whole (mosaic) and that the same thing fin show that it has a fin structure like suggest that they provide evidence for evolves more than once independently Tiktaalik. fish–tetrapod evolution. Coelacanth (parallel). Both of these are excuses is a prime example. Before it was that are used when common descent are still very much components known that its limbs were used for fails, and are extremely unlikely to of a fin. There remains a large deft manoeuvring of the fin, the happen.9,13 morphological gap between them coelacanth’s limbs were thought to be and digits as seen in, for example, evidence of the fish–tetrapod transition. Conclusion Acanthostega: if the digits evolved 9 Now we know better. The situation is For all the complex 3D imaging from these distal bones, the process no different in Panderichthys. must have involved considerable that went into this paper, there really is not much in it. It further confirms developmental repatterning.’7 The illusion of evolution that Tiktaalik is an unequivocal fish, They do not claim that the Boisvert et al. are rather confused related to Panderichthys, and it tells us digits themselves in Panderichthys as to how and where to place that fish–tetrapod evolution is a mess. are any more advanced than Tiktaalik; Panderichthys in the evolutionary This is not a surprise from a biblical but they do claim that some of the series: perspective, because evolution fails features of the so-called ‘wrist’ and ‘It is difficult to say whether this to explain the evidence, and these fish the positioning of the digits are more character distribution implies were created fully functional. tetrapod-like. However, they also that Tiktaalik is autapomorphic,10 acknowledge that Panderichthys and that Panderichthys and tetrapods References 11 Tiktaalik are close in pectoral fin are convergent, o r t h a t 1.
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