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Oral Biofilm Analysis of Palatal Expanders by Fluorescence In-Situ Hybridization and Confocal Laser Scanning Microscopy
Published on: October 20, 2011
Dinosaurian soft tissues interpreted as bacterial biofilms
Thomas G Kaye1, Gary Gaugler, Zbigniew Sawlowicz
1Department of Paleontology, Burke Museum of Natural History, Seattle, Washington, United States of America. tomkaye@u.washington.edu
Plos One
|July 31, 2008
Summary
Bacterial biofilms, not dinosaur soft tissues, are found in fossil bones. These biofilms mimic vessels and cells, offering a simpler explanation for preserved structures in ancient bone.
Area of Science:
- Paleontology
- Microbiology
- Geology
Background:
- Previous research reported "dinosaurian soft tissues" preserved within fossilized bones.
- The nature and origin of these reported tissues have been a subject of scientific debate.
- Understanding fossil preservation mechanisms is crucial for interpreting ancient life.
Purpose of the Study:
- To investigate the in situ presence of reported "dinosaurian soft tissues" using scanning electron microscopy.
- To reinterpret the formation and preservation of structures within fossil bones.
- To provide a more conservative explanation for observed microstructures in fossil specimens.
Main Methods:
- Scanning electron microscopy (SEM) survey of fossil bones from various dinosaur and mammal species.
- Analysis of mineralized and non-mineralized coatings within trabecular bone.
- Infrared spectroscopy comparison of modern biofilms, modern collagen, and fossil bone coatings.
- Carbon dating of preserved organic films.
Main Results:
- Extensive mineralized and non-mineralized coatings identified as bacterial biofilms were found in fossil bones.
- These biofilms form endocasts that mimic blood vessels and osteocytes after dissolution.
- Carbon dating indicated a modern origin for the biofilm material.
- Infrared spectra showed greater similarity between fossil coatings and modern biofilms than modern collagen.
Conclusions:
- The structures previously interpreted as "dinosaurian soft tissues" are likely fossilized bacterial biofilms.
- Biofilms provide a more parsimonious explanation for the observed microstructures in fossil bones.
- This reinterpretation challenges previous assumptions about soft tissue preservation in dinosaurs.
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