Using CT to Peer into the Past: 3D Visualization of the Brain and Ear Regions of Birds, Crocodiles, and Nonavian Dinosaurs

  • Lawrence M. Witmer
  • Ryan C. Ridgely
  • David L. Dufeau
  • Molly C. Semones


Until relatively recently, information on the internal skull structures of fossil taxa relied on fortuitous breaks, aggressive removal of rock matrix (Galton 1989, 2001), sectioning with a saw (Osborn 1912), or serial ground thin-sectioning (Stensiö 1963), all of which potentially risk damage to the fossil specimen (or even consume it entirely in the case of ground thin-sections). In some cases, casts of internal structures, such as the brain cavity and labyrinth of the inner ear, were preserved as ‘natural endocasts’ by infilling with more resistant matrix (e.g., Newton 1888). In most cases, however, physical endocasts are made after matrix removal by coating internal cavities with latex and then removing the cured replica, referred to as a latex endocast (Radinsky 1968; Jerison 1973; Hopson 1979). The process of making latex endocasts poses further risks to the fossil, and for many fragile specimens, such an approach has been unfeasible.


Dorsal View Semicircular Canal Color Plate Nerve Canal Left Lateral View 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer 2008

Authors and Affiliations

  • Lawrence M. Witmer
    • 1
  • Ryan C. Ridgely
    • 1
  • David L. Dufeau
    • 2
  • Molly C. Semones
    • 3
  1. 1.Department of Biomedical Sciences and College of Osteopathic MedicineOhio UniversityAthensUSA
  2. 2.Department of Biological SciencesOhio UniversityAthensUSA
  3. 3.Honors Tutorial CollegeOhio UniversityAthensUSA

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