Biofilm Micro-Environments In Dinosaur Bone

Dinosaur bone preserved in the Hell Creek and Lance formations does not generally mineralize the fossil into a solid mass. The spongy trabecular bone in these fossils maintain open voids which provide a cave-like microenvironment for the formation of bacterial biofilms. A scanning electron microscope survey of these micron scale voids identified various types of microstructures both biotic and abiotic. These structures consist of spheres, motile bacteria trackways, preserved gas bubbles, mineralized coatings and biofilm endocasts which survive after the dissolution of the original substrate. The origin of these microstructures is not at all obvious and objects with similar morphology such as ‘spheres' can result from both biologic and inorganic processes. Proper identification requires prior knowledge of identifying characteristics, and may dictate other analytical techniques such as energy dispersive spectroscopy. These micro-environments offer the potential for future discoveries and contain some truly bizarre microstructures. Biofilms have further implications for detection of life on Mars. Vugs, known to be present on Mars, would be an opportune place to search for mineralized biofilms as long lasting signs of extraterrestrial micro-life.