Exploring the biogeochemistry and evolution of new branches on the tree of life
Brett Baker, University of Texas at Austin
Our understanding of the ecology, evolution, and physiological capabilities of most microbes is hampered by a lack or cultured representatives and the seemingly limitless biodiversity in nature. To overcome this problem, we have sampled anoxic environments around the world, including hot springs, estuaries, and deep-sea sediments. We have reconstructed thousands of genomes that comprise dozens of new branches on the tree of life, including several new phyla. For example, several phyla belonging to a new superphylum, the Asgard archaea, are revolutionizing our understanding of the origin of eukaryotes. These genomes enable us to infer the metabolisms of new organisms and has revealed that many of these new taxa play crucial roles in marine carbon and nutrient cycling. We are also leveraging this genomic-centric community wide comparison to understand how ecological roles are partitioned in marine sediments.