July 30, 2008 (Creation-Evolution Headlines) — The claim made in 2005 that soft tissues in dinosaur bone had been discovered (see 03/24/2005) has been challenged by new research published in PLoS One.1  Maybe the pliable stuff is just slime.

Thomas Kaye from the Burke Museum of Natural History in Seattle with two colleagues were actually hoping to find more soft tissue samples.  After analysis, they concluded instead that what they saw in both dinosaur bone, turtle and ammonite fossils is bacterial biofilm that grew in the hollow spaces inside the fossils.  This challenges the findings of Mary Schweitzer’s team who not only claim to have found flexible tissues and remnant blood vessels, but had also sequenced collagen protein in the samples (04/12/2007).  Kaye interprets the putative iron-rich blood cell remnants as framboids – microscopic mineral spheres.  Finding similar structures in an ammonite (squid-like animal with a shell) and turtle indicated to the team that these framboids were too common to be examples of exceptional preservation from the original tissue.  Instead, they postulate that bacterial biofilms grew inside and around the original tissue, maintaining the shape of it after it had decayed away.  The paper was summarized by Science Daily, PhysOrg and Reuters.

According to New Scientist, though, Schweitzer is not convinced.  Her studies indicated that the dinosaur collagen resembled that of chicken, and the mammoth collagen resembled that of elephants.  Kaye offered no explanation for how that could happen, she said.  Other scientists quoted in the article conjectured that the tissues could be composites of both original tissue and biofilm.  The Reuters article quotes Kaye as saying, “We are not experts in the field.  We are not disagreeing with the fact that their instruments detected protein.  We are offering an alternative explanation.”…

We asked a dozen follow-up questions in the 11/11/2006 entry when the slime interpretation was first raised.  More questions come to mind now.  Why was biofilm inside fossilized bone discovered now, after centuries of collecting fossils?  Is there something in common with the environments displaying this phenomenon?  What did all the scraping, grinding and pressing do to the original material?  Maybe less destructive techniques need to be used for corroboration.  Even if biofilms can conform to original tissues and persist after they decay away or fossilize, is it reasonable to believe they would remain unaltered for 68 million years?  If the biofilms date modern by radiocarbon methods, and bacteria are still seen swimming around, it would have to imply the bacteria have been sitting there all this time, incorporating carbon-14 as they grow and divide millions of times.  What did they live on after the original tissue was all gone?  Wouldn’t there be evidence of millions of generations of biological growth in the bacterial colony?  How reasonable is it to assume that for 68 million years, a biofilm would maintain such a good mimic of original dinosaur tissue (now long gone) that it would fool careful researchers in the lab?…

This is a scientific controversy in progress.  It illustrates the tentative nature of scientific announcements.  The biofilm advocates might argue that Schweitzer’s soft-tissue interpretation is the extraordinary claim that demands extraordinary evidence.  One should take a conservative, guarded attitude about it till more observations can test it.  Fine; creationists were going strong without dinosaur soft tissue.  Their views do not require it.  It would be very interesting to them if the soft-tissue interpretation wins out, and they could employ it as additional evidence falsifying millions of years.  Even so, their claims were no less robust before the surprise announcement in 2005.  Creationists don’t need the soft tissue, but evolutionists need their millions of years.  As we have argued, the biofilm interpretation, even if it wins out, does not get rid of their difficulty.

More… (source)