Amber Fossils Revealed by Synchrotron Imaging

International audienceAmber is of great paleontological value because it preserves a diverse array of organismsfrom different habitats in and close to the amber-producing forests. Terrestrial arthropods arethe most commonly preserved inclusions but, in rare instances, amber also contains smallmollusks, reptiles, birds, feathers, mammal hairs, plants, and various microbes. Thus, amberdiscoveries help tracing the evolutionary history of lineages with otherwise poor fossilrecords, and they also provide insight into the diversity and ecology of terrestrialpaleoecosystems.Inclusions in translucent amber are commonly studied using standard opticalmicroscopes, but the minute size as well as the position of inclusions in an amber piece canprevent the full morphological and anatomical views. Moreover, a significant portion of amberis partly or fully opaque, and biological inclusions in such amber are invisible. Synchrotronimaging techniques are powerful tools to access such poorly exposed and invisibleinclusions1. An optimized imaging protocol has been developed2, using propagation phasecontrast X-ray synchrotron microradiography to efficiently survey large amounts of opaqueamber after immersion in water, followed by phase contrast microtomography for precisecharacterization of selected organisms.REFERENCES1. P. Tafforeau et al. 2006. Appl. Phys. A: Mater. 83, 195-202 (2006).2. M. Lak, D. Néraudeau, A. Nel, P. Cloetens, V. Perrichot and P. Tafforeau, Microsc. Microanal. 14, 251-259 (2008)