Solid modeling of fossil small mammal teeth

doi:10.1016/j.cageo.2010.07.011

Computers & Geosciences

Volume 37, Issue 9, September 2011, Pages 1364-1371

https://doi.org/10.1016/j.cageo.2010.07.011 Get rights and content

Abstract

This paper presents an approach to create solid models of fossil small mammal teeth using a combination of microcomputed tomography, object based image analysis and voxel modeling. Small mammal teeth, because of their durability, are widely found in Cenozioc sediments the world over and play a key role in stratigraphy as well as in researching the rapid evolution and the paleogeographic spreading of small mammals. Recent advances in microcomputed tomography make this non-destructive analysis method an ideal data source for high-resolution 3D models of fossil small animal teeth. To derive internally consistent solid models of such fossils from micro-CT imagery, we propose a combination of 3D object based image analysis and solid modeling. Incorporating paleontological expert knowledge in the image processing cycle, object based image analysis yields topologically consistent image stacks classified by the main tooth components—enamel, dentine and pulp. Forwarding these data to a voxel modeling system, they can be quantitatively analyzed in an unprecedented manner: going beyond the possibilities of the state-of-art surface models, solid models are capable of unambiguously portraying the entire object volume—teeth can be peeled by material properties, subvolumes can be extracted and automatically analyzed by Boolean operations. The proposed method, which can be flexibly extended to handle a range of paleontological and geological micro-objects, is demonstrated with two typical fossil small mammal teeth.

Section snippets

Introduction and paleontological background

Being the most resistant parts of mammal skeletons, teeth frequently provide the sole record of fossil species: when bones have already been destroyed, teeth can still be found. The mammal tooth consists of root(s) and crown. The root anchors the tooth in the jaw, and the crown is adapted to various chewing mechanisms, to cutting, crushing or grinding of food. Enamel, the shiny material covering the dentine part of the crown is the hardest tissue a vertebrate body can produce. It protects the

SMT fossils

A set of six low and high crowned molar teeth (average length 2 mm) from upper Miocene small mammals was selected to check the potential of μCT for SMT analysis. From this set, we chose two samples: a second lower molar of Microtocricetus molassicus and a first upper molar of Vasseuromys pannonicus from the Upper Miocene of Austria. The dormouse Vasseuromys represents the typical lophodont and brachyodont glirid-dental pattern which persisted almost unchanged from the Eocene to the present.

Summary

In this article, we have presented a combination of micro-computed tomography, object based image analysis and solid modeling for the comprehensive portrayal of the internal architecture of fossil small mammal teeth. μCT as an inherently three-dimensional, rapid and destruction-free analysis method outputs stacks of high-resolution grey level images. To pave the way to consistent 3D solid models of SMT, the partially noisy μCT images with abundant artifacts are processed by OBIA, incorporating

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Solid modeling of fossil small mammal teeth

Abstract

Section snippets

Introduction and paleontological background

SMT fossils

Summary

ISRPS Journal of Photogrammetry and Remote Sensing

ISPRS International Journal of Photogrammetry and Remote Sensing

Computers and Geosciences

Computers and Geosciences

Definiens cognition network technology—a novel multimodal image analysis technique for automatic identification and quantification of biological image contents

Progressing from object-based to object-oriented image analysis

Practical cone-beam algorithm

Journal of the Optical Society of America

Continental-scale hypsodonty patterns, climatic paleobiogeography and dispersal of Eurasian Neogene large mammal herbivores

Deinsea

The corpus callosum in schizophrenia—volume and connectivity changes affect specific regions

NeuroImage