Electronic media greatly enhance the ability to visualize multidimensional observations arising from paleontological studies. Lyons and Head (1998) were the first to illustrate the power of multimedia and interactive graphical tools for visualization of microfossils in taxonomic research (and more examples have become available since then). The study presented herein is an example where the advantages of animated scenes are exploited for a set of morphometric measurements, in this case of the Miocene to Recent coccolithophorid Calcidiscus leptoporus. For this organism, an extended set of morphometric data representing the past 23 million years exists (Knappertsbusch 2000). In that study, the hypothesis of punctuated equilibrium (Eldredge and Gould 1972) was evaluated. Nine morphotypes of C. leptoporus were distinguished on the basis of coccolith size and number of radial elements on the distal side of the coccoliths. During time-series analysis of these data an interesting microevolutionary pattern emerged showing several intervals of frequency-mode separation (=cladogenetic events) in the morphospace of the measurements through time, including phases of unidirectional phyletic change and periods of stasis.

The interpretation of these data, however, was difficult, and comprehensive visualization of the observed microevolutionary trends to a wider audience persisted as a real challenge. Showing the data in two dimensions or treatment of the data with traditional statistical procedures always led to a loss of interesting details of the phylogenetic relationships between morphotypes. Early attempts to illustrate these data with an interactive graphics and data-plotting program capable of display in three dimensions (MacSpin) were premature (in the early 1990's) because of the lack of technology for electronic mediation. At that time, the only possibility was to document the pattern in printed media with the risk that many interesting aspects of C. leptoporus morphological evolution would remained obscure.

In Knappertsbusch (2000) various techniques were explored to document the morphological evolution of C. leptoporus in printed form. Although the morphological variability of this species through time could be illustrated, these techniques are rather abstract and remain less understandable to non-specialists. With the advent of graphical software tools for publication of animated scenes in the internet, such difficulties have now vanished. Complex data sets can now be illustrated in a more comprehensive way. The goal of the present contribution is to exploit the electronic medium to illustrate the evolutionary history of C. leptoporus with the help of animated scenes and to document their construction in order to demonstrate alternative ways of presenting morphometric data. Some of these illustrations are also prepared as stereo diagrams (anaglyphs), and can be watched in three dimensions with the help of red-green glasses. The source of the raw data, together with the derived data and software tools (all in the public domain), that were necessary for the construction of the animations, are given so that specialists can experiment and explore the C. leptoporus data set further. In this context the present contribution is not a duplication of existing results, but provides useful supplementary information about the evolution of C. leptoporus that is not otherwise available to the scientific community.

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