Will do ... because I want to know how much their story changed from "This" -
Soft tissue found in 75 million-year-old dinosaur bones is a big deal for paleontology
After they had some time to work on that story.
And all they came up with was ...
"The discovery could have a big impact on fossilization science. "Before this discovery, as a palaeontologist,
I ‘knew’ that it was not possible for soft tissues to be preserved over geologic timescales, except in exceptionally rare circumstances,"
AND what made them "KNOW" that??
Maidment explains. "What is most exciting for me is the potential this opens up: if we are able to find these tissues in other specimens, and replicate the results, it indicates this type of preservation might even be the ‘norm.'"
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"Later, Schweitzer recalls, “I looked at this and I looked at this and I thought, this can’t be. Red blood cells don’t preserve.”
Schweitzer showed the slide to Horner. “When she first found the red-blood-cell-looking structures, I said, Yep, that’s what they look like,” her mentor recalls. He thought it was possible they were red blood cells, but he gave her some advice: “Now see if you can find some evidence to show that that’s not what they are.”
What she found instead was evidence of heme in the bones—additional support for the idea that they were red blood cells. Heme is a part of hemoglobin, the protein that carries oxygen in the blood and gives red blood cells their color. “It got me real curious as to exceptional preservation,” she says. If particles of that one dinosaur were able to hang around for 65 million years, maybe the textbooks were wrong about fossilization.
=============== which was stated this way "at the time" in 2005
""We have several indications that the structures we found are consistent with red blood cells and collagen," explains Sergio Bertazzo, a physical chemist at Imperial College London and co-author of
the study published in
Nature Communications today. "We were not expecting to find what we found at all. So for us, every single discovery was quite exciting."
casting about them for ways to "explain-away" what is not expected:
"There's one important limitation that's worth noting, however. It's possible that the red blood cells don't belong to the dinosaurs at all, Bertazzo says; contamination from other animals can't be ruled out"
"This
isn't the first such discovery; researchers have been able to find soft tissues like this in other fossils. What sets this study apart is the fact that the researchers were able to find these materials despite the fact that the fossils weren't exceptionally well preserved. And before this finding, the researchers note in the study, the oldest un-degraded collagen ever recorded was about
4 million years old."
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DNA Decay Rate Evaluated
"By measuring the length of remaining mitochondrial DNA fragments, the team calculated the half-life of meaningfully sequenceable DNA.
DNA half-life for a 242 base pair strand was 521 years, indicating a decay rate about 400 times slower than predicted. The researchers suspect that nuclear DNA decays considerably faster. They also reported that despite the rough correlation to radiocarbon-determined ages, there was a great deal of variation, possibly due to varying conditions during the process of fossilization. Nevertheless, extrapolating their calculations to other possible scenarios, they suggest that soft tissue preserved at –5 ºC might harbor DNA fragments about 30 base pairs long for considerable lengths of time, possibly allowing preservation of a meaningful amount of DNA in million-year old specimens,
but not 65–million-year-old ones"
