DECOMPOSITION PATHWAYS OF MICROBIAL COMMUNITIES AND MATS

Taphonomic processes, like bacterial decomposition, commonly alter organisms prior to their fossilization. Actualistic experiments performed in the laboratory can be used as an analog to better understand the changes caused by these processes. Previous work has established decomposition pathways for monocultures of filamentous and coccoidal microorganisms. In contrast, this experiment observes morphological changes to cultures of mixed cyanobacteria and algae during bacterial decomposition. Microbial mats were also grown in the lab from purchased kits and observed during decomposition. After the addition of natural freshwater and seawater, the microbial mixtures were observed for morphological changes over the course of several weeks. Changes to individual microorganisms are classified as TG Good, TG Fair, and TG Poor. This same methodology is being performed on individual microbes within the various layers of the mats. Results of this actualistic experiment are compared to other experiments performed on monocultures and silicified Mesoproterozoic microbial mats.