Aprendo en Línea Ministerio de Educación Chile
Soft tissue found inside a dinosaur bone!
In 2003, an exceptionally well preserved T. rex leg bone was unearthed in the Cretaceous rocks of Montana. Upon close examination, Dr. Mary Schweitzer found the bone to contain soft tissue inside - tiny blood vessels and proteins! Some claim that this is evidence of a young Earth, a recent extinction of the dinosaurs. Could this be, or is there another explanation? ============= Update: since writing the script for this video, a new study came out that weakens the consensus that the tissue found belongs to the original T. rex: http://rspb.royalsocietypublishing.org/content/284/1855/20170544 ============= ======== Support us on Patreon: https://www.patreon.com/statedclearly Get a T. rex t-shirt: https://www.redbubble.com/people/statedclearly/works/28105774-gloating-t-rex?asc=t&p=t-shirt Visit Dr. Mary Schweitzer’s website: https://molecularpaleo.wordpress.ncsu.edu/ ======== Papers cited in this animation: ORIGINAL DISCOVERY OF SOFT TISSUE: Soft Tissue Vessels and Cellular Preservation in Tyrannosaurus rex: http://science.sciencemag.org/content/307/5717/1952 Soft tissue and cellular preservation in vertebrate skeletal elements from the Cretaceous to the present: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1685849/ CRITIQUE OF DISCOVERY: Dinosaurian Soft Tissues Interpreted as Bacterial Biofilms: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2483347/ DEFENSES OF DISCOVERY: Influence of Microbial Biofilms on the Preservation of Primary Soft Tissue in Fossil and Extant Archosaurs: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2953520/ Molecular analyses of dinosaur osteocytes support the presence of endogenous molecules: http://www.thebonejournal.com/article/S8756-3282(12)01318-X/fulltext Testing the Hypothesis of Biofilm as a Source for Soft Tissue and Cell-Like Structures Preserved in Dinosaur Bone: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4771714/ 10 million year old frog bones with marrow preserved: https://pubs.geoscienceworld.org/geology/article-abstract/34/8/641/129601/high-fidelity-organic-preservation-of-bone-marrow?redirectedFrom=fulltext IRON’S ROLE IN PRESERVATION: A role for iron and oxygen chemistry in preserving soft tissues, cells and molecules from deep time: http://rspb.royalsocietypublishing.org/content/281/1775/20132741 OTHER DINOSAURS WITH SOFT TISSUE DISCOVERED: Mass Spectrometry and Antibody-Based Characterization of Blood Vessels from Brachylophosaurus canadensis: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4768904/ Evidence of preserved collagen in an Early Jurassic sauropodomorph dinosaur revealed by synchrotron FTIR microspectroscopy: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5290320/ Soft sheets of fibrillar bone from a fossil of the supraorbital horn of the dinosaur Triceratops horridus: https://www.ncbi.nlm.nih.gov/pubmed/23414624 Hemoglobin-derived porphyrins preserved in a Middle Eocene blood-engorged mosquito: https://www.ncbi.nlm.nih.gov/pubmed/24127577 Molecular preservation in Late Cretaceous sauropod dinosaur eggshells https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1599869/
Analizar e interpretar datos para proveer de evidencias que apoyen que la diversidad de organismos es el resultado de la evolución, considerando:
- Evidencias de la evolución (como el registro fósil, las estructuras anatómicas homólogas, la embriología y las secuencias de ADN).
- Los postulados de la teoría de la selección natural.
- Los aportes de científicos como Darwin y Wallace a las teorías evolutivas.
Curso: 1° Medio
Asignatura EG: Ciencias Naturales
Tipo: Videos
Colección: Youtube: CURRICULUM MINEDUC