Ultrastructural Approaches to the Microfossil Record: Assessing Biological Affinities by Use of Transmission Electron Microscopy

  • Sebastian Willman
  • Phoebe A. Cohen
Part of the Topics in Geobiology book series (TGBI, volume 36)


One of the major technological advances in biological research was the invention and development of the transmission electron microscope, which enables high resolution and high magnification studies of cross-sections of specimens. As such, it has proved to be a useful tool to describe ultrastructural features of taxonomic and phylogenetic importance in modern organisms. Here we discuss how to extend the use of transmission electron microscopy (TEM) to the fossil record, with emphasis on acritarchs (organic-walled microfossils of unknown affinity). Microfossils are traditionally studied by use of transmitted light microscopy, a method that reveals details of external morphology only. TEM however, gives an additional level of detail and reveals structures that can greatly aid in interpretation of taxonomic affinity, and thus can reveal further detail on the origination and diversification of myriad eukaryotic groups in the fossil record. In this chapter we describe the preparation procedure, show advantages and shortcomings of the technique, and discuss how to interpret the results from a geobiological perspective.


TEM Ultrastructure Preparation Acritarch Biological affinities 



Gary Wife, Anette Axén and Stefan Gunnarsson at the Microscopy and Imaging unit at EBC, Uppsala University, are thanked for their expertise regarding preparing and sectioning the samples and microscope work. Margaret Coughling at the Harvard Medical School provided help and inspiration to PAC in developing a new preparation method and provided help and advice with microtoming.


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Copyright information

© Springer Netherlands 2011

Authors and Affiliations

  1. 1.Department of Earth Sciences, PalaeobiologyUppsala UniversityUppsalaSweden
  2. 2.Department of Earth and Planetary SciencesHarvard UniversityCambridgeUSA
  3. 3.Massachusetts Institute of TechnologyNASA Astrobiology InstituteCambridgeUSA

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