Before revision: This coincided with a global glaciation (which might also have been partly caused by the depletion of the atmospheric methane — a powerful greenhouse gas — due to the Great Oxygenation) and devastated the anaerobic archaeal biota, leaving the niches open for eubacteria (both the aerobic proteobacteria and the photosynthetic cyanobacteria) to exploit and prosper.
After revision: ice age known as the HuronianThis coincided with a global glaciation (which might also have been partly caused by the depletion of the atmospheric methane — a powerful greenhouse gas — due to the Great Oxygenation) and devastated the anaerobic archaeal biota, leaving the niches open for eubacteria (both the aerobic proteobacteria and the photosynthetic cyanobacteria) to exploit and prosper.