A5039264979- Paleontology and Evolutionary Biology
- Evolution and Paleontology Studies
- Ichthyology and Marine Biology
- Pleistocene-Era Hominins and Archaeology
- Amphibian and Reptile Biology
- Morphological variations and asymmetry
- Turtle Biology and Conservation
- Wildlife Ecology and Conservation
- Paleontology and Stratigraphy of Fossils
- Avian ecology and behavior
- History of Science and Natural History
- Species Distribution and Climate Change
- Genetic diversity and population structure
- Genomics and Phylogenetic Studies
- Isotope Analysis in Ecology
- Advanced Proteomics Techniques and Applications
- Bone and Dental Protein Studies
- Identification and Quantification in Food
- Comparative Animal Anatomy Studies
- Geological and Geochemical Analysis
- Spaceflight effects on biology
- Cell Adhesion Molecules Research
- Geology and Paleoclimatology Research
- Glycosylation and Glycoproteins Research
- Historical Studies in Science
North Carolina State University
2016-2025
North Carolina Museum of Natural Sciences
2015-2025
Museum of the Rockies
1999-2023
Montana State University
2002-2023
Lund University
2015-2023
Beth Israel Deaconess Medical Center
2007-2008
Harvard University
2007-2008
Wellcome Centre for Cell-Matrix Research
2008
Center for Systems Biology
2007
Geophysical Laboratory
2004-2005
Fossilized bones from extinct taxa harbor the potential for obtaining protein or DNA sequences that could reveal evolutionary links to extant species. We used mass spectrometry obtain of a 160,000- 600,000-year-old mastodon (Mammut americanum) and 68-million-year-old dinosaur (Tyrannosaurus rex). The presence T. rex indicates their peptide bonds were remarkably stable. Mass can thus be determine unique ancient organisms fragmentation patterns, valuable tool study evolution adaptation which...
We performed multiple analyses of Tyrannosaurus rex (specimen MOR 1125) fibrous cortical and medullary tissues remaining after demineralization. The results indicate that collagen I, the main organic component bone, has been preserved in low concentrations these tissues. findings were independently confirmed by mass spectrometry. propose a possible chemical pathway may contribute to this preservation. presence endogenous protein dinosaur bone validate hypotheses about evolutionary...
The Birds and the Dinosaurs extent to which primary tissues are preserved in ancient fossils remains controversial. Schweitzer et al. (p. 626 ; see news story by Service ) describe well-preserved collagen sequences from femur of an 80-million-year-old hadrosaur. fossil structures resembling bone vessels. Both extracts tissue pieces were analyzed multiple laboratories mass spectrometry, revealed that support a close relation between birds dinosaurs.
Soft tissues are preserved within hindlimb elements of Tyrannosaurus rex (Museum the Rockies specimen 1125). Removal mineral phase reveals transparent, flexible, hollow blood vessels containing small round microstructures that can be expressed from into solution. Some regions demineralized bone matrix highly fibrous, and possesses elasticity resilience. Three populations have cell-like morphology. Thus, some dinosaurian soft may retain their original flexibility, elasticity,
Unambiguous indicators of gender in dinosaurs are usually lost during fossilization, along with other aspects soft tissue anatomy. We report the presence endosteally derived bone tissues lining interior marrow cavities portions Tyrannosaurus rex (Museum Rockies specimen number 1125) hindlimb elements, and we hypothesize that these homologous to specialized avian known as medullary bone. Because is unique female birds, its discovery extinct solidifies link between suggests similar...
Exceptionally preserved fossils—i.e., those that retain, in some manner, labile components of organisms are normally degraded far too quickly to enter the fossil record—hold greatest potential for understanding aspects biology long-extinct animals and best targets search endogenous biomolecules. Yet modes preservation these components, exactly what remains original composition, not well understood. Here, I review a selection cases soft tissue Mesozoic vertebrates, examine chemical...
Soft tissues and cell-like microstructures derived from skeletal elements of a well-preserved Tyrannosaurus rex (MOR 1125) were represented by four components in fragments demineralized cortical and/or medullary bone: flexible fibrous bone matrix; transparent, hollow pliable blood vessels; intravascular material, including some cases, structures morphologically reminiscent vertebrate red cells; osteocytes with intracellular contents filipodia. The present study attempts to trace the...
The persistence of original soft tissues in Mesozoic fossil bone is not explained by current chemical degradation models. We identified iron particles (goethite-αFeO(OH)) associated with recovered from two dinosaurs, using transmission electron microscopy, energy loss spectroscopy, micro-X-ray diffraction and Fe absorption near-edge structure. Iron chelators increased tissue immunoreactivity to multiple antibodies dramatically, suggesting a role for both preserving masking proteins tissues....
Sequence data from biomolecules such as DNA and proteins, which provide critical information for evolutionary studies, have been assumed to be forever outside the reach of dinosaur paleontology. Proteins, are predicted greater longevity than DNA, recovered two nonavian dinosaurs, but these results remain controversial. For proteomic derived extinct Mesozoic organisms their greatest potential investigating questions phylogeny paleobiology, it must shown that peptide sequences can reliably...
Abstract Medullary bone (MB), an estrogen-dependent reproductive tissue present in extant gravid birds, is texturally, histologically and compositionally distinct from other types. Phylogenetic proximity led to the proposal that MB would be non-avian dinosaurs recent studies have used microscopic, morphological regional homologies identify this both theropod ornithischian dinosaurs. Here, we capitalize on unique chemical histological fingerprint of birds characterize, at molecular level,...
The modifications that occur on proteins in natural environments over time are not well studied, yet characterizing them is vital to correctly interpret sequence data recovered from fossils. recently extinct moa (Dinornithidae) an excellent candidate for investigating the preservation of proteins, their post-translational (PTMs) and diagenetic alterations during degradation. Moa protein extracts were analysed using mass spectrometry, peptides collagen I, II V identified. We also identified...
Significance We report fossil evidence of feather structural protein (beta-keratin) from a 130-My-old basal bird ( Eoconfuciusornis ) the famous Early Cretaceous Jehol Biota, which has produced many feathered dinosaurs, early birds, and mammals. Multiple independent molecular analyses both microbodies associated matrix recovered feathers confirm that these are indeed melanosomes. use transmission electron microscopy immunogold to show localized binding antibodies raised against filaments...
Microbodies associated with fossil feathers, originally attributed to microbial biofilm, have been reinterpreted as melanosomes: pigment-containing, eukaryotic organelles. This interpretation generated hypotheses regarding coloration in non-avian and avian dinosaurs. Because melanosomes microbes overlap size, distribution morphology, we re-evaluate both hypotheses. We compare within feathers of extant chickens patterns induced by overgrowth on the same using scanning (SEM), field emission...
Structures similar to blood vessels in location, morphology, flexibility, and transparency have been recovered after demineralization of multiple dinosaur cortical bone fragments from specimens, some which are as old 80 Ma. These structures were hypothesized be either endogenous the (i.e., vascular origin) or result biofilm colonizing empty osteonal network degradation original organic components. Here, we test hypothesis that these thus retain proteins common with extant archosaur can...
Dinosaur fossils possessing integumentary appendages of various morphologies, interpreted as feathers, have greatly enhanced our understanding the evolutionary link between birds and dinosaurs, well origins feathers avian flight. In extant birds, unique expression amino acid composition proteins in mature been shown to determine their biomechanical properties, such hardness, resilience, plasticity. Here, we provide molecular ultrastructural evidence that pennaceous Jurassic nonavian dinosaur...
Abstract The idea that original soft tissue structures and the native structural proteins comprising them can persist across geological time is controversial, in part because rigorous testable mechanisms occur under natural conditions, resulting such preservation, have not been well defined. Here, we evaluate two non-enzymatic protein crosslinking mechanisms, Fenton chemistry glycation, for their possible contribution to preservation of blood vessel recovered from cortical bone a...
Other| June 01, 2003 Remarkable Preservation of Undigested Muscle Tissue Within a Late Cretaceous Tyrannosaurid Coprolite from Alberta, Canada KAREN CHIN; CHIN 1Department Geological Sciences and CU Museum, University Colorado at Boulder, UCB 265, CO 80309. Karen.Chin@colorado.edu Search for other works by this author on: GSW Google Scholar DAVID A. EBERTH; EBERTH 2Royal Tyrrell Museum Palaeontology, Box 7500, Drumheller, Alberta T0J 0Y0, MARY H. SCHWEITZER; SCHWEITZER 3Department...
We report small fibrous structures associated with a new specimen of Shuvuuia deserti, which we hypothesize are remnants feather-like epidermal appendages. Multiple analyses suggest that these epidermally derived and contain epitopes consistent beta-keratin, protein expressed only in extant "reptiles" birds. Morphological, microscopic, mass spectrometric, immunohistochemical studies the interpretation related to feathers. These data proteinaceous components may survive across geological time...
The application of high-resolution analytical techniques to characterize ancient bone proteins requires clean, efficient extraction obtain high quality data. Here, we evaluated many different protocols from the literature on ostrich cortical and moa evaluate their yield relative purity using identification antibody-antigen complexes enzyme-linked immunosorbent assay gel electrophoresis. Moa provided an comparison for effectiveness tested bone. For immunological part this study, focused...
In the mid-19th century, discovery that bone microstructure in fossils could be preserved with fidelity provided a new avenue for understanding evolution, function, and physiology of long extinct organisms. This resulted establishment paleohistology as subdiscipline vertebrate paleontology, which has contributed greatly to our current dinosaurs living Dinosaurs are part larger group reptiles, Archosauria, there only two surviving lineages, crocodilians birds. The goal this review is document...
The holotype (MHM-K2) of the Eocene cheloniine Tasbacka danica is arguably one best preserved juvenile fossil sea turtles on record. Notwithstanding compactional flattening, specimen virtually intact, comprising a fully articulated skeleton exposed in dorsal view. MHM-K2 also preserves, with great fidelity, soft tissue traces visible as sharply delineated carbon film around bones and marginal scutes along edge carapace. Here we show that extraordinary preservation type T. goes beyond gross...