If I'm pinging you it's because either I spoke to you about this, think I spoke to you about this, or think you might be interested. ;-)
I am writing to you because I feel that your coverage of Dr. Schweitzer's dinosaur fossil research has been grossly unfair and misleading. AIG has misrepresented Dr. Schweitzer's research, slandered Dr. Schweitzer and her colleagues by accusing them of attempting to "explain away" their findings, and swept under the rug a follow-up paper published by Dr. Schweitzer which presents some inconvenient evidence indicating that birds and theropod dinosaurs are genetically related.
My letter is prompted by your March 6 article "The Scrambling Continues" regarding Dr. Schweitzer's discovery last year of an unusually well-preserved Tyrannosaurus rex fossil femur. When the fossil was retrieved the femur was broken. The internal cavity had an unusual porous appearance, so Dr. Schweitzer took some small fragments of the bone and soaked them in a solution that removed all of the minerals. It is important for the sake of accuracy to emphasize that the samples removed from the fossil were indeed hard and mineralized, not soft like raw marrow as some sources have stated (based I believe on your misleading commentary). After the minerals were removed the end products were tiny fragments (most less than 1/8 inch in diameter) of a network, with some fragments (or sections of a fragment) brittle and fragile while other fragments were spongy and flexible, resembling connective tissue and blood vessels. Under the microscope in the vessels Dr. Schweitzer could see structures resembling cells and with some type of internal structure. I'll quote the conclusion of Dr. Schweitzer's paper (1):
"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. If so, in addition to providing independent means of testing phylogenetic hypotheses about dinosaurs, applying molecular and analytical methods to well-preserved dinosaur specimens has important implications for elucidating preservational microenvironments and will contribute to our understanding of biogeochemical interactions at the microscopic and molecular levels that lead to fossilization."
AIG has reported this recovered material as strictly organic. This is a conclusion not warranted by the evidence, as a close reading of Dr. Schweitzer's original article and even a cursory reading of the accompanying commentary article (2) in the same issue of Science would show:
"Hendrik Poinar of McMaster University in Hamilton, Ontario, cautions that looks can deceive: Nucleated protozoan cells have been found in 225-million-year-old amber, but geochemical tests revealed that the nuclei had been replaced with resin compounds. Even the resilience of the vessels may be deceptive. Flexible fossils of colonial marine organisms called graptolites have been recovered from 440-million-year-old rocks, but the original material--likely collagen--had not survived."
Some of the tougher biopolymers (especially chitin, lignins and proteins) may degrade very slowly in a fossil. Some arthropod fossils from 25 million years ago contain a small amount of chitin (3), although insects preserved in amber from about the same time period show complete diagenetic alteration (fossilization) in spite of the superb morphological preservation (4). Likewise, in spite of the excellent morphological preservation of this fossil Dr. Schweitzer clearly states that it is unknown at this time whether the actual original cellular and organic material is present. The preservation of intact organic material from a long-extinct species would be a wonderful scientific find, however it is most likely that Dr. Schweitzer and other molecular paleontologists will have to settle for studying the typical biomolecule degradation products found in fossils (5). It may actually be that some fraction of organic matter was preserved, and the supplemental material Dr. Schweitzer published indicates that this may be true as the sample extracts showed some affinity for antibodies against bovine osteocalcin and chicken type I collagen. This leads to the exciting possibility of extracting collagen or other structural proteins from the T. rex sample and comparing these to avian proteins to help clarify the evolutionary relationship between birds and theropod dinosaurs. However, it is unfortunately more likely that the sample will prove to be fully mineralized and lacking any utilizable amount of untransformed biomolecules. If this is so AIG will have egg in its face after its trumpeting of the T. rex sample as "unfossilized soft tissue" ("Still Soft and Stretchy," 25 March 2005).
When I read "The Scrambling Continues" it led me to see if any new papers on this fossil have been published since last year. Sure enough, my search revealed a Science paper from June 2005 (6). This paper is foreshadowed by a line in the initial paper: "In addition to the dense compact bone typical of theropods, this specimen contained regions of unusual bone tissue on the endosteal surface." I'll quote from the June paper:
"The location, origin, morphology, and microstructure of the new T. rex tissues support homology with ratite MB [medullary bone]. The T. rex tissues line the medullary cavities of both femora of MOR 1125, suggesting an organismal response. The tissues are similar in distribution to those of extant ratites, being more extensive in proximal regions of the bone. They are clearly endosteal in origin, and the microstructure with large vascular sinuses is consistent with the function of MB as a rapidly deposited and easily mobilized calcium source. The random, woven character indicates rapidly deposited, younger bone. Finally, the robustly supported relationship between theropods and extant birds (15–18, 24, 25) permits the application of phylogenetic inference to support the identification of these tissues (26, 27)."
Medullary bone is a particular type of bone laid down in the endosteal cavities of female birds to allow storage and rapid mobilization of calcium for egg-laying. This type of bone has only been found in birds, so its discovery in a dinosaur fossil ought to be noteworthy to anyone interested in science. This uniquely avian trait in T. rex adds another piece of evidence supporting the evolutionary origin of birds from theropod dinosaurs. I'm certain that your researchers must have run across this article while checking to see if Dr. Schweitzer had published a follow-up paper. Your failure to mention this article's findings in your rather snide article indicates to me that AIG is not so much interested in the pursuit of knowledge as the promulgation of anti-evolutionary propaganda.
Now I have the benefit of prior knowledge of your likely response to this finding of medullary bone in a dinosaur. I mentioned my complaints about your coverage to a young-earth creationist, and he emailed you asking about this. He shared with me your response, which was that medullary bone was indeed found in other species besides birds, providing these links as support: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1790209&dopt=Abstract, http://cal.vet.upenn.edu/saortho/chapter_53/53mast.htm. These links can be easily found by either searching Google for "medullary bone" and ignoring the multiple hits saying it is uniquely avian or by searching for "medullary bone" and excluding "avian" and "bird." The first example given is actually a misunderstanding by your staff member of basic bone growth--in a young mammal the interior of the bone is filled with spongy bone which recedes to leave a medullary cavity as the bone grows. The second example is talking about the medullary cavity and adjacent structures--it describes "medullary bone infarct," which usually occurs in the medullary cavity near the end of a long bone and results in bone marrow and trabecular bone necrosis. Both of these instances have nothing to do with avian medullary bone. Genuine medullary bone is produced by a genetically encoded organismal response to gonadal hormones in an adult female bird, leading to the deposition of bone in the medullary cavity. The gross and microscopic appearance of medullary bone is unique, and the structural composition is quite different from other types of bone (7). Indeed, osteoblasts isolated from hen medullary bone show different expression patterns of genes than osteoblasts isolated from rats, indicating that avian medullary osteoblasts are uniquely differentiated and the process of medullary bone deposition is different than mammalian bone formation (8). The fossilized bone recovered from this T. rex show unequivocal avian medullary bone, and pose quite a conundrum for those who deny evolutionary relationships.
I can hardly expect AIG to suddenly embrace an old earth and common descent. However, I'm sure that AIG would want to be seen as a trustworthy organization that can be relied upon to present the facts accurately. In light of this I am requesting that you publish a correction stating that the T. rex fossil discovered was extensively fossilized, did not have a "raw" appearance, and that the flexible fragments recovered are tiny (on the order of 1/8 inch). Additionally I request an acknowledgment of the existence of Dr. Schweitzer's paper reporting the discovery of avian medullary bone in the T. rex fossil. Finally, I request that my letter in whole be published on your site. These steps will go far towards correcting AIG's superficial coverage of Dr. Schweitzer's findings.
Thank you for your attention to these matters.
Well, I learned something (actually quite a bit) from your letter.
Anyone making bets as to who else learned and who choses to obfucate?
"However, it is unfortunately more likely that the sample will prove to be fully mineralized and lacking any utilizable amount of untransformed biomolecules."
Thanks. Maybe another example of sensationalism.
You wrote this almost two weeks ago and we have this thread here just today so we must have been snoozing when this all first was announced.
I liked your letter, it was pointed and direct; who knows, maybe AIG will publish it.
I wonder has she done MALDI-mass-spec on some of the material, yet. That would be a pretty good indication of the state of the organic material.
Surely you're not suggesting that the pseudo science creationists would deliberately mislead the flock about the state of the evidence they're pretending to do scientific research on are you? I'm shocked! Shocked, I tell you!