T. rex Fossil Yields Soft Tissue

T. rex Fossil Yields Soft Tissue, High Resolution Photo of Fragments of soft tissue extracted from the marrow cavity of a T. rex femur, after the surrounding bone mineral has been dissolved away. (A) The demineralized fragment is flexible and resilient and, when stretched (arrow), returns to its original shape. (B) Demineralized bone in (A) after air drying. The overall structural and functional characteristics remain after dehydration. (C) Regions of demineralized bone show fibrous material (arrows). Scale bars: 0.5 mm.Credit: From Schweitzer et al., Science 307:1952-1955 (2005). Reprinted with permission from AAAS.

In a discovery that invokes comparisons to Jurassic Park, North Carolina State University paleontologist Mary Schweitzer and her colleagues have extracted soft tissue from the fossilized leg bone of a 70-million-year-old Tyrannosaurus rex specimen. The soft tissue includes intact, still-flexible blood vessels and fibrous material consistent with collagen. Also, electron microscopy reveals round-to-oval bodies virtually identical to the cell nuclei found in the corresponding tissues of ostriches, which, along wtih other birds, are believed to be modern-day descendants of dinosaurs.

Whether the tissue will yield DNA or any other biomolecules remains to be answered.

Schweitzer and her team published the finding in the March 25 issue of the journal Science.

The presence of this novel tissue is not the only surprise from this discovery, says Enriqueta Barrera, a program director in the National Science Foundation's earth sciences division, which partly funded the study. The tissue was once elastic and stretchy, and had the capacity to be dehydrated and rehydrated many times without losing this characteristic. “Although the preservation of soft tissue such as this is not unique in the geologic record, this occurrence goes well beyond what has been observed in the past for dinosaurs, and reinforces the evolutionary link of dinosaurs to birds,” said Barrera.

For more information, see the NC State news release. -NSF-

Media Contacts Cheryl L. Dybas, NSF (703) 292-7734 cdybas@nsf.govTracey Peake, NC State (919) 515-3470 tracey_peake@ncsu.edu, Program Contacts Enriqueta Barrera, NSF (703) 292-8551 ebarrera@nsf.gov, Principal Investigators Mary H. Schweitzer, NC State (919) 515-3711 schweitzer@ncsu.edu, Related WebsitesThe Science paper: sciencemag.org/-NSF- Press Release 05-048, SOURCE: National Science Foundation