GEOBIOLOGY AND PALEOGENOMICS

Geobiology is centered on interactions of the biosphere with the atmosphere, hydrosphere, and lithosphere. In deep time geobiology has focused on critical intervals of change for Earth and its biota. Such geobiological studies include data from paleontology, geochemistry and sedimentary geology within an interdisciplinary framework. Paleogenomics has a variety of research agendas, and one of them is to understand the genes involved in key changes in the evolutionary history of life and when those genes first evolved. The combination of geobiology and paleogenomic studies is a powerful approach which leads to a more fundamental understanding of how Earth and life have changed through time. In current research such combined studies are most advanced in efforts to understand the early evolution of animals and the Cambrian explosion. For example, linking paleogenomic studies of biomineralization genes in modern organisms and when they first evolved in the Cambrian with geobiological studies of the impact this had on the production of carbonate sedimentary facies and the development of the Neritan Ocean provides a unique perspective. The remaining Phanerozoic includes a broad variety of evolutionary innovations which within a joint geobiological and paleogenomic context can also be profitably studied. In marine benthic environments these include the changes in the echinoid genome that led to widespread burrowing euechinoids and associated sedimentary and biogeochemical changes. Similarly, identification of the genes which allow scleractinian corals to turn formation of the skeleton on and off during periods of changing ocean chemistry have great utility for understanding reef development. In pelagic environments the genomic changes leading to biomineralized coccolithophores and planktonic foraminifera led to the widespread deposition of carbonate sediment in deep settings and development of the Cretan Ocean. On land linking paleogenomic studies of the genes that led to the development of lignin and flowers in plants and feathers in dinosaurs, and their associated geobiological effects, has been effective, with great future potential. Such work will ultimately provide a history of genomic change and the environmental factors that influenced it, as well as how genomic change influenced environments.