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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!
This news over a year and a half old!! Someone correct me if I'm wrong, but wasn't this found to be sensationalist the first time around?
Javascript + Nintendo DSi = DSiCade
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).
That's what I wondered... at the end of May, so it's old news now. And yes, I submitted it as a story, but it was rejected.
Btw, bye.
I dream of a better world... one in which chickens can cross roads without their motives being questioned.
If every other dinosaur bone had soft tissue, this wouldn't be news.
That debate ended when we figured out carbon dating. The bones are old as their radioactivity says they are.
If this were a matter of carbon dating, then the fossils really are truely very young.
Carbon dating is not reliable at all. It was a mistake for it to be used and trusted so much. Now all these assumptions of age are base on flawed data. http://www.drdino.com/articles.php?spec=79
Meme's aside
Can we 'start a meme that you don't use apo'strophe's in every word that end's in "'s" plea'se?
Thank you for the very nice article(!), but I have to correct you here, there are no amino acids in DNA. What they mean in the article is that the degree of racemisation (the process of going from all left to mixed left-right) of amino acids originating from proteins in the cell, is an indication of the degree of damage to the cell in general. So if amino acid racemisation is present, they know that probably the DNA will be in a crappy state as well and they can skip the sample.
molmod.com - computing tips from a molecular modeling
In the book, they used reptile and frog DNA, some of everything, figuring the vast majority of the DNA would be the same for dinos, other reptiles, and amphibians. The movie kept it simple with, "We filled in the gaps with frog DNA..."
But according to TFA (and other discoveries of the past decade), the best choice would probably have been ostrich DNA.
The article will lead us to believe that a bone was cracked, and fresh dino blood spilled out. Nothing could be further from the truth.
m l and http://www.talkorigins.org/faqs/dinosaur/blood.htm l
Please read this http://www.talkorigins.org/faqs/dinosaur/flesh.ht