Terreneuvian

From Palaeos.org

The Terreneuvian or Early Cambrian was a time of great change across a wide spectrum, from tectonic (the breakup of the early Rodinia and Pannotia supercontinents) through geographical (marine transgressions as the ocean invaded the land creating shallow continental seas that allowed primitive life to flourish), atmospheric (rising oxygen and falling carbon dioxide levels), biogeochemical (changing ocean chemistry, promoting biomineralization; especially the upwelling of high phosphorous levels, enabling organisms to develop skeletons of calcium phosphate), and ecological (the appearance of predation and algae grazers, which meant an end of the Ediacaran idyll). This combination of events would seem to have been responsible for the sudden and remarkable diversification of metazoan life at this time.