The Great Oxygenation Event (GOE), ca. 2.4 billion years ago, transformed life and environments on Earth. This paper mathematically analyzes the GOE, considering ecological dynamics coupled with planetary changes. Anoxygenic photosynthetic bacteria initially dominated, but their success depended on electron donors vulnerable to oxidation. The GOE is triggered when the difference between reductants and phosphate influxes falls below a critical value. The transition's nature (gradual/reversible or sudden/irreversible) depends on oxygen sources and sinks. Increasing sources and decreasing sinks can trigger the GOE, but this relies heavily on cyanobacteria migration. The model links ecological dynamics to geophysical evolution, determining relevant timescales.

Jason Olejarz, Yoh Iwasa, Andrew H. Knoll, Martin A. Nowak