The Great Ordovician Biodiversification Event (GOBE) was a spectacular evolutionary radiation of marine life that occurred during the Ordovician period, roughly 40 million years after the Cambrian explosion. While the Cambrian explosion established the basic animal body plans (phyla), GOBE filled those blueprints with a vast array of families, genera, and species, tripling marine biodiversity. The event saw a dramatic rise of filter-feeders, bryozoans, corals, brachiopods, trilobites, and giant cephalopods. The complexity of marine food webs increased, with organisms pioneering new ecological niches by burrowing deeper into the seafloor sediment or venturing higher into the open water column, shaping the structure of marine ecosystems for millions of years.