Molecular geomicrobiology: Genes and geochemical cycling

Core geosciences concepts are being fundamentally revised as the result of breakthroughs in geomicrobiology. Revolutionary discoveries have resulted from increased effort devoted to study of microorganisms in the context of their environments. Much recent progress has been made possible by genetic data, particularly those that allow the description of microbial populations in situ. New gene and genome sequences are elucidating previously unexpected or unexplained interactions between microorganisms and Earth materials, with implications for key geological phenomena such as the formation of ore deposits and the regulation of global climate and surface oxidation state. Genetic data have also led to extensive revision of our understanding of the pace and mechanisms by which evolution occurs. Yet, the field of molecular geomicrobiology remains in its infancy. In the foreseeable future, merging of modern biogeochemistry with molecularly resolved ecological studies will inspire the development of integrated models for the processes that shape the Earth.