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Calcified Tissue International

, Volume 74, Issue 2, pp 162–169 | Cite as

An Examination of Triassic Cynodont Tooth Enamel Chemistry Using Fourier Transform Infrared Spectroscopy

  • J. BothaEmail author
  • J. Lee–Thorp
  • M. Sponheimer
Laboratory Investigations

Abstract

The Cynodontia are considered to be particularly significant as their remains document the reptile-to-mammal transition during the Permian and Triassic periods. Studies examining cynodont morphology and anatomy have shown that these animals acquired increasingly mammal-like characteristics during their evolution. In this study, we use Fourier Transform Infrared spectroscopy to assess the enamel structure of several Triassic cynodonts. Extant Crocodylus niloticus and Varanus enamel spectra as well as published extant and fossil mammalian data were used as comparisons. The profiles of the cynodont spectra resemble biological apatite, in spite of their great age. The ratio of structural carbonate to phosphate in these cynodonts is significantly higher than in the extant and fossil mammals, but very similar to the extant reptiles. We suggest that the enamel apatite structure of these cynodonts was more similar to the reptilian rather than the mammalian pattern.

Keywords

Tooth Enamel Therapsid Cynodont Fourier Transform Infrared spectroscopy 

Notes

Acknowledgements

We gratefully acknowledge the following for the loan of the material: R. Smith and D. Ohland of the South African Museum, Iziko Museums of Cape Town; B. Rubidge and M. Raath of the Bernard Price Institute for Palaeontological Research, University of Witwatersrand, Johannesburg; and J. Clack from the University of Cambridge, England. We also thank Jurie Prins of Le Bonheur Crocodile Farm for the crocodile teeth. The National Research Foundation of South Africa funded this research.

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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  1. 1.Karoo Palaeontology, Natural History DivisionSouth African Museum, Iziko Museums of Cape Town, Cape TownSouth Africa
  2. 2.Archaeometry Research UnitUniversity of Cape Town, Rondebosch, Cape TownSouth Africa
  3. 3.Department of BiologyUniversity of Utah, Salt Lake City, UT 84112USA

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