A NEW AGE IN PALEOBIOLOGY: APPLICATIONS OF ADVANCED MICROBEAM INSTRUMENTATION IN FOSSIL ANALYSES

Over the past decade, advanced microbeam instruments have been migrating beyond the boundaries of the materials science industry—gaining popularity across many scientific disciplines, certainly including geo- and paleobiology, for micro- and nanoscale analyses. The goal of this presentation is to serve as a primer for understanding the capabilities of many of these tools, ranging from commonly available instruments, such as environmental scanning electron microscopy (ESEM), to specialized technologies, including focused ion beam electron microscopy (FIB-EM). Many of the previously used and currently applied paleobiological methods in which these microbeam instruments have been/are being used to examine the fossil preservational pathways, isotopic signatures, and micro- and ultrastructures (among others) of ancient and evolutionarily significant fossils will be reviewed and discussed. Specifically included examples of research coming from the Virginia Tech Institute for Critical Technology and Applied Science Nanoscale Characterization and Fabrication Laboratory will be the utilization of ESEM and integrated energy dispersive X-ray spectroscopy in characterizing a mode of Ediacaran fossilization with the aid of microbe-particle interactions (Laflamme et al., 2009, GSA Abstracts); the use of secondary ion mass spectroscopy in examining the authigenic sequence and potential role of sulfate-reducing bacteria in the formation of Ediacaran pyrite-rimmed chert nodules (Xiao et al., 2009, GSA Abstracts) as well as assessing growth rates, ontogeny, and longevity of Paleozoic blastoids (Dexter et al., 2008, GSA Abstracts); and finally applications of FIB-EM in examining three-dimensionality of Mesoproterozoic acritarch ultrastructures (Schiffbauer and Xiao, 2009, PALAIOS) and additionally reproducing and examining predatory microtraces produced by the radulae of drilling gastropods (see Schiffbauer et al., 2008, PALAIOS; Schiffbauer et al., 2009, NAPC Abstracts). We hope to demonstrate that advanced microbeam instruments and contemporary techniques are powerful and useful tools in the micro- and nanoscale investigation of fossil taphonomy, chemical composition, and construction—and will contribute to our understanding of a diversity of evolutionarily significant organisms.