July 13, 2006 | David F. Coppedge

Cambrian Mollusk: Does It Help Animal Evolution Story?

A soft-bodied mollusk named Odontogriphus known from the Burgess Shale, placed in the Middle Cambrian, has been described in more detail in Nature.1  If the Middle Cambrian is well after the Cambrian explosion, how can the authors claim this pushes the story of animal evolution far back into the Precambrian, before the explosion?  A reporter for the Globe and Mail learned this from David Rudkin, one of the four co-authors of the paper:

This discovery pushes back the history of animal evolution tens of millions of years to 560 million years ago in Precambrian time (543 million years ago and earlier), according to the Royal Ontario Museum’s David Rudkin, co-author of the article published in today’s issue of the journal Nature.

This interpretation is based on perceived similarities with Kimberella, an unusual flattened, frond-like fossil categorized as Ediacaran (see 08/19/2004), dated at 555 million years ago in the late Precambrian.  Yet a look at the original paper shows that the association is tenuous: “Odontogriphus and perhaps the Ediacaran form Kimberella possess distinctive characters that place them in the molluscs before the acquisition of a calcified dorsum,” it says.  It qualifies the association with prefaces like, “If the interpretation of Kimberella as an early mollusc-like organism with radula is correct,” and portrays affinities with other early and mid-Cambrian mollusk fossils as “ambiguous” and “highly contentious.”
    A look at their timeline chart demonstrates the point.  There are more dashed lines and question marks than solid lines.  All the indisputable mollusk fossils are found in the early or mid Cambrian, side by side.  The evolutionary relationships are inferred by dashed lines extending into the Precambrian, with no fossils except for the puzzling Kimberella, which may have nothing to do with mollusks.
    Moreover, the Globe and Mail article admits that very few fossils exist from the Precambrian, and that the Cambrian “marked the sudden appearance of complex multicellular macroscopic organisms” (see 04/23/2006).  It also states that “In the Precambrian era, before the so-called explosion, organisms were thought to be much simpler, but this study shows that was not the case.”  The paper describes these organisms as possessing a nervous system, a digestive system, reproductive system, excretory system, salivary glands and neat rows of teeth (radula).  Nor is Odontogriphus the new kid on the block.  The authors describe it as a holdover from “a handful of Cambrian fossils that probably represent surviving Neoproterozoic lineages” that survived whatever made the Ediacaran biota go extinct.
    Such statements would seem to pose severe challenges to evolutionary theory, yet the news report speaks glowingly of how this fossil is helping evolutionists rather than hurting their case.  “This is a crucial interval in evolutionary history because it seems to represent a time in which a great deal happened,” Rudkin is quoted as saying.  He added that the specimen is “opening up new windows on evolution for us.”  The article ends with a call for us to learn the lessons of evolution:

Mr. Rudkin said the fact that many mollusks have survived such a catastrophic extinction could shed light on the evolutionary path many animals may take.
    “Those lessons we learn from the past — about where groups of organisms originated, when they become extinct, how they became extinct, or if they didn’t become extinct entirely, how they recovered from extinction — we use that kind of historical background to help us predict what might happen in modern extinction circumstances.  Maybe there’s a lesson in there for us.

1Caron et al., “A soft-bodied mollusc with radula from the Middle Cambrian Burgess Shale,” Nature 442, 159-163(13 July 2006) | doi:10.1038/nature04894; Received 15 February 2006; Accepted 8 May 2006.

The lesson is not to tell myths and call it science.  This paper registered multiple hits on our Baloney Detector.  Enough baloney, and you have a virtual big lie.
    These extinct mollusks with all their complex parts have nothing to do with evolution.  If this is a window on evolution, it’s a new view of the wreckage.  How scientists can take evidence that falsifies their view and turn it into praise service for Charlie is another example of the shameful shenanigans of the shameless Darwin Party these days.  Their shifty shell game is a sham and should be shot down by those who respect real science sans spin.

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Categories: Fossils

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