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Soft Tissue Discovered In T-Rex Bone
kubla2000 writes, "Paleontologists have discovered soft tissue inside the fossilized thigh bone of a T-Rex. The tissue included blood vessels, bone cells, and perhaps even blood cells." From the article: "When paleontologists find fossilized dinosaur bones during a dig, they usually do everything in their power to protect them, using tools like toothbrushes to carefully unearth the bones without inflicting any damage. However, when scientists found a massive Tyrannosaurus rex thigh bone in a remote region of Montana a few months ago, they were forced to break the bone in two in order to fit it into the transport helicopter. This act of necessity revealed a startling surprise: soft tissue that had seemingly resisted fossilization still existed inside the bone. This tissue... was so well preserved that it was still stretchy and flexible."
Dude, this is a YEAR OLD! And slashdot ran this exact same story last year. Look at the dates on the pictures!
Credit: From Schweitzer et al., Science 307:1952-1955 (2005). Reprinted with permission from AAAS.
Geez!
You're right that it's old news. It was a bit sensationalist in that it's not really soft tissue but rather a stable polymerization of the soft tissue. Still, it remains an important discovery, and I'm still waiting for more follow-up.
In your obvious haste to be first to point this out you clearly just linked to the first source you found on a simple search, which is a nutty creationist website. How about a slightly less wacky news source?
- "Hear that?! The percolations are imminent! Cease your ingress!"
This is more like the recent bestseller "Tyrannosaur Canyon" by Douglas J Preston than it is like Jurassic Park. That book involves the discovery of a complete T Rex fossil with soft tissue.
Where were you when the voynix came?
DNA isn't an especially robust molecule. It probably didn't survive that long. It is prone to a variety of reactions that will degrade it over time relatively quickly. Though it was originally thought to survive much longer, DNA older than a million years is now considered pretty dubious, and is likely contamination from other sources, such as soil microbes, or it is degraded fragments with no meaningful signal left in them (e.g., older DNA extracted from fossils tens of millions of years old contains roughly equal left and right amino acids, whereas living tissues contain all left ones, implying the DNA has been severely degraded). Previous discoveries from fossils tens of millions of years old (e.g., from old amber) have proven unreproducible. There's a good review in this PDF format paper by Hofreiter et al., 2001.
By contrast, some organic molecules, such as collagen, are much more durable than DNA, and could plausibly survive much longer in the right conditions, such as if embedded in the minerals that form bone. This general fact has been known for a long time (those papers are from the 1960s and are both PDFs), though how old such remains might ultimately be found is still uncertain. Also, even if the organic molecules were severely degraded, it doesn't mean they vanish completely -- some degraded C-bearing organic residue might remain as long as it wasn't dissolved away, and it could still preserve the shape of the original tissues, even if it wasn't compositionally the same anymore.
Some organic molecules are extraordinarily durable and occur as fossils routinely. The sporopollenin that forms the cell wall of spores and pollen is like the "plastic garbage bag" of organic materials. It can survive multiple passages through the digestive system of animals, and still be intact. Fossil pollen and spores are often recovered from sedimentary rocks essentially unchanged, except for a bit of thermal alteration, and geologists use potent acids like concentrated HCl and HF to dissolve the minerals away, but the pollen and spores are untouched!
Finally, even if the organic molecules themselves get destroyed (e.g., it isn't, say, collagen anymore), minerals could precipitate in contact with the soft tissues and preserve their shape at microscopic scale. The soft tissue isn't actully there, but the structure is. Such preservation is rare, but is known for other types of soft tissues in an older dinosaur (the linked example of the dinosaur Scipionyx does show soft-tissue structures, such as intestines, but they are all mineralized).