Dating dinosaur fossils
Dating dinosaur fossils - Free sex nitna
Called heme units, these chemically stable structures consist of a ringlike organic compound called porphyrin bound to an iron atom.
In the next few years, she analyzed some other fossils from the age of dinosaurs, finding evidence for preservation of some keratin proteins from fossil claws and from feather-like fibers.
Thus, we could not claim definitively that they were blood cells.
When we published our findings in 1997, we drew our conclusions conservatively, stating that hemoglobin proteins might be preserved and that the most likely source of such proteins was the cells of the dinosaur.
Porphyrins derived from chlorophyll have been found in sediments dating back to the Carboniferous, when vast forests blanketed the planet many millions of years before the dinosaurs existed.
So we did not think it too far-fetched that heme units from hemoglobin might still exist in our T. Also, the responses of immune systems of laboratory mice to injections of powdered dinosaur bones suggested that the bones “contained something similar to the hemoglobin in living animals”.
In 2010, she wrote an article, “Blood From Stone”, in fossil skeleton.
She saw what looked like red blood cells – they were “the right size, shape and color to be blood cells, and they were in the right place, too.” This was a surprise, since “The conventional wisdom holds that when an animal dies under conditions suitable for fossilization, inert minerals from the surrounding environment eventually replace all of the organic molecules—such as those that make up cells, tissues, pigments and proteins—leaving behind bones composed entirely of mineral.” Were these actually red blood cells, or the chemically transformed remains of red blood cells, or merely artifacts of some unknown geological process that produced rounded blobs of material?
She noted  that keratin proteins “are good candidates for preservation because they are abundant in vertebrates, and the composition of this protein family makes them very resistant to degradation.” This work was published in 1999.
Again, it was largely ignored, since her findings “challenged everything scientists thought they knew about the breakdown of cells and molecules.
This sounds amazing – – “fresh”, “soft, squishy tissues” and “pliable blood vessels, red blood cells, and proteins”. Here are the topics treated below: 1992: Mary Schweitzer Sees What Looks Like Red Blood Cells 2004: Schweitzer Finds Bits of Soft Tissue in T.
This verbiage makes the reader think that someone cracked open these dinosaur bones and found raw tissue flopping around inside, dripping with red blood cells. Rex Bones 2006 Onward: Sequencing Proteins from Dinosaur Bones Mechanisms for Ancient Protein Preservation Osteocyte Cells, Traces of DNA, and Iron as a Preservative Assessment of Evidence That Soft Tissue Can Persist for 70 Million Years Invariance of Radioactive Decay Rates The Dinosaur-Bird Connection Mary Schweitzer on Creation Conclusions ************************************************ 1992: Mary Schweitzer Sees What Looks Like Red Blood Cells Key discoveries in this area over the past twenty years have been made by Mary Schweitzer, now a professor of paleontology at North Carolina State University.
Soft Tissue in Dinosaur Fossils: Evidence for a Young Earth?