– Manuscript – Life on Earth faced an extreme test of survivability during the Cryogenian Period, which began 720 million years ago. The planet was frozen over most of the 85 million-year period. Scientists say Earth would have looked like a shiny white snowball in space during the deep freeze. But life somehow survived during this time called "Snowball Earth." A … [Read more...] about Study Explains How Life Survived the ‘Snowball Earth’ Period