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Darwinists’ Obsession with Tiktaalik Linked to Lack of Transitions in the Fossil Record

monkeyseemonkeydo.jpgMedia see, media do. And when it comes to the fossil record, the elite Darwinists of late seem unable to see evidence that challenges evolution. With the National Academy of Sciences (NAS) and PBS forcefully promoting Tiktaalik to the public as proof of an evolutionary transition from fish to land-walking animals, the media is following closely in their footsteps (no pun intended). A recent article on Canada.com pushes a pro-evolution book titled “Your Inner Fish,” which tries to use Canadian- found fossil Tiktaalik to promote evolution and influence American presidential politics. It’s the Canadian Darwinist’s dream. But this is strange behavior: why are the scientific elite so forcefully pushing this one fossil, especially when it so poorly documents the evolution of the key aspect of the transition of fish into land-animals: the transformation of fins to feet? The answer lies in what PBS, the NAS, and the media are not telling the public about the fossil record.

Following in the scientific elite’s footsteps, the media is failing to mention the fact that the pattern in the fossil record is not one of transitional forms, but of explosions of mass biological diversity without plausible evolutionary transitions. As one textbook states: “Many species remain virtually unchanged for millions of years, then suddenly disappear to be replaced by a quite different, but related, form. Moreover, most major groups of animals appear abruptly in the fossil record, fully formed, and with no fossils yet discovered that form a transition from their parent group.” But you won’t hear groups like the NAS or PBS admit any of this when they talk to the general public about evolution.

ID proponents are willing to boldly go where no Darwinist dares to go–to discuss the explosions in the history of life. At The Design of Life Blog, Denyse O’Leary recently documented how the history of life is full of explosions of biological diversity that challenge a Darwinian explanation. O’Leary also blogged about the newly revealed Avalon explosion, where a group of pre-Cambrian organisms (not thought to be ancestors of the Cambrian organisms) appear without any clear evolutionary precursors.

Following the scientific elite, the media ignore explosions in the fossil record and instead emphasize one or two fossils that ultimately serve as unconvincing examples of transitional forms. The media have also missed the fact that after evolutionists discover some new alleged transitional fossil, they suddenly feel comfortable enough to be quite candid about the lack of fossils previously documenting that alleged transition. This too is suspicious behavior. To recount the media behavior, Darwinist behavior, and real evidence surrounding Tiktaalik, the media’s new darling of the fossil record, I’m reposting an analysis of Tiktaalik from when this fossil was first reported in the spring of 2006:

I love it when new “missing links” are discovered, because it’s then–and only then–that Darwinists admit how precious little evidence had previously existed for the evolutionary transition in question. When reports came out this week of an alleged example of a fossil representative of the stock that might have led from fish to tetrapods — Tiktaalik roseae — evolutionists finally came clean about the previous lack of fossil evidence for such a transition:

“The relationship of limbed vertebrates (tetrapods) to lobe-finned fish (sarcopterygians) is well established, but the origin of major tetrapod features has remained obscure for lack of fossils that document the sequence of evolutionary changes.”

(Edward B. Daeschler, Neil H. Shubin, and Farish A. Jenkins, “A Devonian tetrapod-like fish and the evolution of the tetrapod body plan,” Nature Vol 440: 757-763 (April 6, 2006))

Authority Jennifer Clack even admits that before finding Tiktaalik, the large morphological gap between fish and true tetrapods was “frustratingly wide”:

“It has long been clear that limbed vertebrates (tetrapods) evolved from osteolepiform lobefinned fishes3, but until recently the morphological gap between the two groups remained frustratingly wide. The gap was bounded at the top by primitive Devonian tetrapods such as Ichthyostega and Acanthostega from Greenland, and at the bottom by Panderichthys, a tetrapod-like predatory fish from the latest Middle Devonian of Latvia (Fig. 1).”

(Jennifer A. Clack & Per Erik Ahlberg, “A firm step from water to land,” Nature 440:747-749 (April 6, 2006); emphasis added)

Again Daeschler et al. reiterate the lack of evidence previous fossils provide for a transition, focusing on deficiencies in what was previously considered to be the closest fish to tetrapods (see the diagram below as well):

Panderichthys possesses relatively few tetrapod synapomorphies, and provides only partial insight into the origin of major features of the skull, limbs and axial skeleton of early tetrapods. In view of the morphological gap between elpistostegalian fish and tetrapods, the phylogenetic framework for the immediate sister group of tetrapods has been incomplete and our understanding of major anatomical transformations at the fish-tetrapod transition has remained limited.”

(Edward B. Daeschler, Neil H. Shubin, and Farish A. Jenkins, “A Devonian tetrapod-like fish and the evolution of the tetrapod body plan,” Nature Vol 440: 757-763 (April 6, 2006))

Walk Off The Stage, Acanthostega
The previous darling of the “fish-to-tetrapod” transition-representatives was Acanthostega gunnari–a true tetrapod. Acanthostega has extremely tetrapod-like limbs, feet (with a few extra fingers), and a pelvic girdle. This little guy was a star of the PBS Evolution‘s episode II: “Great Transformations,” where Jenny Clack called it a “fish with fingers” (The only problem is that Acanthostega wasn’t a fish–as Daeschler et al. correctly categorize it as a non-fish tetrapod, contrasting “Skull roofs of elpistostegalian fish and the early tetrapod Acanthostega” [Nature 440:759]. Even Clack, quoted above, calls it a “tetrapod” and distinguishes it from fishes, making one wonder what was going on when PBS Evolution showed her calling it a “fish with fingers”.)

But only now that we have Tiktaalik will we hear evolutionists boast about the size of the previously large “gap” in this transition, and how Tiktaalik solves all these previously unanswered questions. I’m super skeptical that this new fossil is good evidence that a transition took place: Acanthostega was truly a tetrapod, but Tiktaalik is a fish. As Clack and Ahlberg write, there’s still a large gap (and any usefulness a fin had for walking was the result of a lucky pre-adaptation):

There remains a large morphological gap between them and digits as seen in, for example, Acanthostega: if the digits evolved from these distal bones, the process must have involved considerable developmental repatterning. The implication is that function changed in advance of morphology.” (Clack & Ahlberg, Nature 440:748; emphasis added).

I think that Figure 4 from, “The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb” (by Neil H. Shubin, Edward B. Daeschler, & Farish A. Jenkins Jr, Nature, Vol 440:764-771 (April 6, 2006)) says it all:

(Adapted by permission from Macmillan Publishers Ltd: “The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb” (by Neil H. Shubin, Edward B. Daeschler, & Farish A. Jenkins Jr, Nature, Vol 440:764-771 (April 6, 2006); figure resized to fit the page except for the text; click for the full figure)

This figure, which Nature graciously has granted permission to reprint, reveals the massive difference in the ray-finned fish-fin of Tiktaalik and the true tetrapod limbs of Acanthostega and Tulerpeton. Is evidence of a transition missing? This new fish fossil doesn’t seem to add much–if anything–to bridge the gap between fish fins and tetrapod limbs. In fact, if anything, the fin of Panderichthys appears closer to a true tetrapod limb than does the fin of Tiktaalik. I would assume that documenting how fins turned into feet would be one of the more important aspects of the fish-to-tetrapod evolutionary story.

In conclusion, this is a fascinating fossil which I’m sure will stir up much debate. But the next time we dig up some fossil of a fin-bound fish (possibly with a few tetrapod-ish characteristics), we’ll hear again all about the previously existing big gaps and how Tiktaalik didn’t really teach us much after all–but how the new fossil solves all the problems. That’s how it usually works, and that makes me wonder where we’re really left today. Anyone who thinks that we’ve found the “missing link” or clear evidence of an evolutionary transition has either forgotten history, or isn’t looking very carefully at the evidence.