https://astrobiology.nasa.gov/news/sustaining-aerobic-eukaryotes-on-snowball-earth/
The snowball effect
https://aeon.co/essays/how-the-harsh-icy-world-of-snowball-earth-shaped-life-today
By Richard Fisher, Graham Shields
For a few times our planet as a harsh, icy world, but that deep freeze didn’t just chill the surface—it helped shape every form of life we know. This article argues that our ancient cold, with its extremes and challenges, nudged evolution, forged resilience, and still colors how we live today. It’s a reminder that even in the toughest environments, life finds a way to adapt and endure.