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A Night in Tax Heaven. (The fishapod failed everywhere else)

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Americans pay taxes for this (PBS via Time.com):

Like it or not, your genes run all the way back to a fishy critter called Tiktaalik that led the way to land 375 million years ago. A new documentary shows why the ancient animal deserves an honored spot in your family tree

Anti-evolutionists have at least one thing in common with climate-change deniers and anti-vaccine nuts: they keep repeating nonsense long after it’s been debunked, and if you debunk it one more time, they pretend they can’t hear you and just keep going. Lather, rinse, repeat—it just never ends.

Actually, we don’t know any of this. Here’s what we know:

Discovered in 2004 in the Canadian Arctic and unveiled in 2006, a 375-million year old fossil of a fish with legs instead of paired fins was hailed as the link between fish and amphibians (frogs, toads, etc.). Evidence suggested that fish had developed legs before walking on land, and speculation abounded as to how or why. In 2009, Nature featured Tiktaalik as No. 2 of 15 Evolutionary Gems. Headlines like “Fossil animals found in Arctic Canada provide a snapshot of fish evolving into land animals,” and “Fossil shows how fish made the leap to land” underlined the find’s importance.

In a PBS documentary, Tiktaalik paleontologist Neil Shubin patiently explains,

What evolution enables us to do is to make specific predictions about what we should find in the fossil record. The prediction in this case is clear-cut. That is, if we go to rocks of the right age, and the rocks of the right type, we should find transitions between two great forms of life, between fish and amphibian. … What we see when we look at the fossil record, at rocks of just the right age, is a creature like Tiktaalik.

But in 2010, Tiktaalik failed the fishapod trials. Apparent tetrapod trackways at least 20 million years earlier (about 397 mya) were reported in Poland (which means that what “evolution” enables us to do had to be hastily revised). Tiktaalik is an interesting fossil, but—if anything other than a fish—not the key transitional fossil Shubin and PBS insisted it is. For some Nature contributors, the trackway discoverers “lob a grenade” into the picture. Tetrapod paleontologist Jenny Clack said the their discovery “blows the whole story out of the water, so to speak.” It is perhaps of interest that some fish, even today, routinely spend time out of the water, using primitive lung apparatus and walking on fins, but there is no particular reason to believe that they are on their way to becoming full time tetrapods or land dwellers.

As so often, the true history of life is sudden emergence. Yet, far from being curious about the persistent pattern, many observers merely hope that the latest upset findings will just be discredited in favour of huffery about “evolution.” Fine, their choice. Nature now postulates that the true transitional fossils exist in a “ghost range”—that is, a period when members of a group should have been present, according to Darwin’s theory, but have not yet been found. [2]

See, the difference between Darwinism’s ghosts and the ones in the tourist trade’s “Ye Olde Haunted Inn” is that you are forced to pay to have the former taught in schools. The latter, yeah, you pay too, but they are good for an appropriate laugh.

[1] Janvier and Clement, “Palaeontology: Muddy tetrapod origins,” Nature 463, 40–41 (7 January 2010) | doi:10.1038/463040a.

[2] For use of the term “ghost range,” see Philippe Janvier & Gaël Clément, “Muddy tetrapod origins,” Nature 463:40-41 (January 7, 2010); ; Grzegorz Niedzwiedzki, Piotr Szrek, Katarzyna Narkiewicz, Marek Narkiewicz & Per E. Ahlberg, “Tetrapod trackways from the early Middle Devonian period of Poland,” Nature, Vol. 463:43-48 (7 January 2010).

6 Replies to “A Night in Tax Heaven. (The fishapod failed everywhere else)

  1. 1
    Joe says:

    If Shubin’s claims had any substance at all he should be able to take fish embryos, subject them to targeted mutagenesis in generation after generation to see if robust bones develop in the fins such that Tiktaalik-type legs appear. And from there continue on to developing a tetrapod.

    Also it is universal common descent, not evolution per se, that leads to specific predictions of transitional forms.

    And I have no doubt that if Shubin had been aware of the tetrapod tracks in Poland then Tiktaalik would have been found in strata older then that- that is the same fossils they now have would have been dated to an earlier period.

  2. 2
    Joe says:

    In “Your Inner Fish” , chapter 3 titled Handy Genes Shubin wrote:

    What if you could do an experiment in which you treated the embryo of a fish with various chemicals and actually changed its body, making part of its fin look like a hand?

    We are still waiting for that experiment. They did take sonic hedgehog from a mouse out it into a fish and it worked, allowing the development of fish parts. SH is just a switch.

  3. 3
    Dionisio says:

    Joe,

    SH is just a switch.

    Just a ‘switch’? like the stuff used in electronic circuitry? the on/off things?

    C’mon buddy, are you joking? are you telling me now that we have switches inside the cells?

    This is biology, not electronics, ok?

    Where would those switches come from? Out of nowhere, just like that? Also, what would turn them on and off? How? When? Why?

    Gimme a break. What a prolific imagination.

    😉

  4. 4
    Dionisio says:

    Now, you want to see an example of the real stuffs?

    Check this out from the Cell journal:

    GeneRegulatoryNetworks GoverningPancreasDevelopment

    H.EfsunArda,1CecilM.Benitez,1andSeungK.Kim1,2,3,* 1DepartmentofDevelopmentalBiology 2HowardHughesMedicalInstitute 3DepartmentofMedicine(Oncology) StanfordUniversitySchoolofMedicine,Stanford,CA94305-5329,USA *Correspondence:seungkim@stanford.edu http://dx.doi.org/10.1016/j.devcel.2013.03.016

    Enjoy it!

  5. 5
    Joe says:

    Dionisio-

    According to evo-devo Sean Carroll the switches came from the (eukaryotic) genetic toolkit.

  6. 6
    Dionisio says:

    Joe,

    Eukaryotic gen toolkit? umm…

    I don’t recall seeing that electronics ‘toolkit’ brand last time I stopped by Radio Shack. It must have been imported from the emerging markets recently ;-).

    Anyway, having a toolkit is a good start, but how does the switch get installed at the right location? How does it get connected to function properly? What about the rest of the circuit components, as well as the topology and layout?
    Wow, it feels kind of weird to talk about electronic circuits relative to biology. 😉
    Things have really gone wild lately 😉

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