We use the evolution of carbon fixation as a model for studying the origin and evolution and processes and pathways. Our work includes genomic studies of the reverse TCA cycle (e.g., here, here and here), methylotrophy (here), Carboxydotrophs (e.g., here), plastid evolution and/or the Calvin cycle (e.g., here, here, here, here, and here), and chemosynthetic symbionts (here, here).