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Author Topic:   Blood in dino bones
Sylas
Member (Idle past 5373 days)
Posts: 766
From: Newcastle, Australia
Joined: 11-17-2002


Message 7 of 138 (194335)
03-25-2005 2:34 AM
Reply to: Message 6 by MangyTiger
03-25-2005 1:33 AM


Re: Read the article more closely...
The major researcher here is Mary Schweitzer, who has been involved in this kind of work now for over ten years. She hit the news in 1997 with a possible detection of heme compounds as remains from dinosaur hemoglobin (Heme compounds in dinosaur trabecular bone, M. Schweitzer et al; PNAS Vol. 94, Jun 1997, pp. 6291-6296) and this was widely and erroneously reported as a find of blood cells and/or complete hemoglobin molecules. There was also an earlier report of possible dinosaur DNA, but that did not pan out. It was almost certainly contamination. She has definitely found some of the more durable proteins (like keratin). The work is fascinating, and she focuses on cases of exceptionally good preservation.
These are highly degraded remains at the molecular level, which have not been fully mineralized and so traces of organic compounds may even remain.
An interesting detail; Schweitzer is a Christian; and she gets very angry at the way her work is used by creationists. Unfortunately, she has not spoken up about this clearly in public. I emailed her some years ago to ask about the heme compounds research, and she expressed a very strong reaction against the creationist misrepresentations on the "blood cells" issue mentioned above. There is no serious question about the age of the fossils.
This particular report is a new one, and it is reported in Science, March 25 2005. The formal reference to the scientific paper is:
Soft-Tissue Vessels and Cellular Preservation in Tyrannosaurus rex
by Mary H. Schweitzer, Jennifer L. Wittmeyer, John R. Horner, and Jan K. Toporski
in Science 25 March 2005; 307: pp 1952-1955 [DOI: 10.1126/science.1108397]
I've looked at the paper. It is quite fascinating, but there is no molecular analysis reported. The preservation appears remarkable, but the extent of relacement is unclear. From the conclusion of the scientific paper:
The elucidation and modeling of processes resulting in soft-tissue preservation may form the basis for an avenue of research into the recovery and characterization of similar structures in other specimens, paving the way for micro- and molecular taphonomic investigations. Whether preservation is strictly morphological and the result of some kind of unknown geochemical replacement process or whether it extends to the subcellular and molecular levels is uncertain. However, we have identified protein fragments in extracted bone samples, some of which retain slight antigenicity (3). These data indicate that exceptional morphological preservation in some dinosaurian specimens may extend to the cellular level or beyond.
ELIZA immunoassays were applied, and submitted as evidence of some molecular level preservation. There were also some elemental analysis, which looks to me to indicate atoms remaining from organic material (high carbon signal).
There was also a commentary article, but my connection broke before I could read it.
Cheers -- Sylas

This message is a reply to:
 Message 6 by MangyTiger, posted 03-25-2005 1:33 AM MangyTiger has not replied

Replies to this message:
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Sylas
Member (Idle past 5373 days)
Posts: 766
From: Newcastle, Australia
Joined: 11-17-2002


Message 13 of 138 (194366)
03-25-2005 4:20 AM
Reply to: Message 12 by simple
03-25-2005 4:10 AM


Re: Read the article more closely...
And since it was rare to open these things up, I wonder how rare it really will turn out to be as every dino bone collector rips them open, looking for more? Ha
Very rare indeed. We already know that; looking inside a fossil is not as uncommon as you suggest. The vast majority of fossils have nothing like this, which is what makes this report so interesting and exciting. The report does actually look at a couple of other well preserved fossils for similar effects, but the main fossil focus of the report was on the one with the best preserved microstructures. Montana seems to be a better place than most for such unusually detailed preservation.
Cheers -- Sylas

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 Message 12 by simple, posted 03-25-2005 4:10 AM simple has replied

Replies to this message:
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Sylas
Member (Idle past 5373 days)
Posts: 766
From: Newcastle, Australia
Joined: 11-17-2002


Message 15 of 138 (194368)
03-25-2005 4:54 AM
Reply to: Message 14 by simple
03-25-2005 4:40 AM


Re: crack em like easter eggs
Sure; it would be great to find more fossils like this, and that will require looking inside. By I don't think anyone, Jack Horner included, expects preservation detail such as reported in Science to be common. The report (he is a co-author) describes the preservation in this fossil as exceptional. But finding more would be a good thing, even if not to quite the same level of detail. Just breaking all fossils open is not the best way to proceed, however. For one thing, it is worth be careful in choosing which fossils to investigate, and for another it needs to be done really carefully to avoid contamination.
Cheers -- Sylas

This message is a reply to:
 Message 14 by simple, posted 03-25-2005 4:40 AM simple has replied

Replies to this message:
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