Two Catastrophes: Snowball Earth & The Permian Extinction

This video is a compilation of two episodes of "Catastrophe," a series of documentaries presented by Tony Robinson in 2008. The first part, "Snowball Earth," is about an episode in Earth's history more than 600 million years ago when the entire planet was encased in snow and ice. This frozen wasteland may have been the birthplace of complex animals as it occurred just before the sudden radiation of multicellular bioforms, known as the "Cambrian explosion." A number of unanswered questions remain, including whether the Earth was a full snowball, or a "slushball" with a thin equatorial band of open (or seasonally open) water. Another, much earlier and longer snowball episode named the Huronian glaciation, occurred 2400 to 2100 million years ago. This cold period may have been triggered by the first appearance of oxygen in the atmosphere, known as the "Great Oxygenation Event." The second part of the video, "The Permian Extinction," is about the Permian-Triassic extinction event, informally known as the "Great Dying." This was an extinction event that occurred much later in time, namely 252 million years ago, forming the boundary between the Permian and Triassic geologic periods, as well as the Paleozoic and Mesozoic eras. It is the Earth's most severe known extinction event, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct. It is the only known mass extinction of insects. Some 57% of all families and 83% of all genera became extinct. Because so much biodiversity was lost, the recovery of life on Earth took significantly longer than after any other extinction event, possibly up to 10 million years. Episodes 1 to 5: https://www.youtube.com/playlist?list=PLpWCFDSTg8dv-td-rl-ryPyvpzKJoKQqj Space and AI https://spaceandai.com