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Re: More soft tissue references

I don't see how broken material exposed to migrating ground water would be useful in this kind of examination. ANY modern contamination would throw off the spectrometers and the tissue cultures. Sealed bone might provide a time capsule for the organics inside but I would bet big money that very little else would. Porous bone fragments would certainly be contaminated by any impurities traveling through the bedrock. However, I bet that this kind of time capsule is not unique by any means. I imagine that there is a combination of events that could lead to more of this type of bone preservation being found by looking for more bones that were recovered deep, of a certain size and type, surrounded by lots of impermeable rock and that were removed from oxygen very soon after burial. OK granted, I suppose by chance situation, any bone fragment could preserve organic remains if there was a sealed cavity within. A significant portion of petrified wood often has partially replaced material on board. Why not bone. Wood is pretty tough to break down though.

I also don't think that this will give any fuel to those literal folks that grasp at straws to promote recent burial. There is nothing contradictory to conventional geologic process here. Just a sealed time capsule from the distant past. Without oxygen and bacterial action, there is nothing to break down the tissues period. Presumably the sealed bone was biologically sterile (except for virus' possibly) upon burial. My only problem with the perfect sealed container idea is that blood supply vessels got into the bone marrow through holes in the bone which must have been sealed immediately by euxinic mud or similar biologically sterile, non oxygen permeable muck. All bone has a blood supply pathway built in I think. Does anyone know of non-vascular bone?
Frank Bliss
MS Biostratigraphy
Weston, Wyoming

On Mar 26, 2005, at 12:17 PM, Jaime A. Headden wrote:

Dora Smith (villandra@austin.rr.com) wrote:

<I am interested in how the tissues were kept int his state of preservation -
but I am quite sure they did not form recently!>

While at first this may seem extraordinary preservation, Mary first uncovered
this by seeing an unusual coloration on a section of tyrannosaur bone, which
she then analyzed more closely, resulting in the current study. In the paper,
she notes how she looked at other fossils, including the Wankel rex and "Sue,"
and found the tissues present there as well, except the resolution of detail
was more profound and ubiquitous in Sue and the first specimen she tested, than
in the Wankel rex. This means that the tissues may be more prevalent than
realized because no one has explicitly tested for them. I beleive she has also
looked at a hadrosdaur fossil and found similar traces, so the material
preservation, while known currently from latest Maastrichtian time in the Hell
Creek Formation, is not confined to either *Tyrannosaurus rex* or even
theropods.

There is another, fuller paper in prep by the authors, so I am sure Mary's
typical thouroughness will reveal itself in how prevalent the material is. This
could also mean that even shattered bone fragements can be scientifically
important, if they could preserve such material. The bone Mary found this on
was a less-than-explary preserved femur, but bone shards can theoretically all
preserve as much detail (my own personal conjecture, not Mary's).

  Cheers,

Jaime A. Headden

Little steps are often the hardest to take. We are too used to making leaps in the face of adversity, that a simple skip is so hard to do. We should all learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)


            
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