Apparent biotic micromorphologies of abiotic origin

摘要

Often, micromorphologies, interpreted as microfossils, provide the first clues to exciting and potentially controversial discoveries related to the early origins of life on the Earth, as well as the potential for life on other planets. It has been said, however, that exceptional claims require exceptional proof, and micromorphological evidence alone may have several possible interpretations, both biotic and abiotic. Garcia-Ruiz, et al. (2003) have shown how silica-coated carbonate crystals in a chert-like matrix can self-assemble inorganically into long folded or braided filaments that closely resemble cyanobacteria fossils thought to be 3.5 billion years old. Recent advances in the field of Materials Science provide numerous other examples of micromorphologies that, due to their complexity and structure, might be misinterpreted as microfossils despite their clearly abiotic origin. Several examples will be discussed. While the chemistries of these abiotic micromorphologies could be considered rather exotic and therefore discounted, the same fossilization process that operates on biotic microorganisms could operate here as well.