Intro

“So many things could have happened in a different way that we wouldn't be here at all, both individually, for sure, and certainly as a species.” What if your existence hinged on two freak accidents? Biologist Sean B. Carroll traces the bizarre chain of events that made human life possible. From an asteroid that wiped out the dinosaurs to a tectonic collision that cooled the planet, Carroll unpacks the unbelievable random events and unpredictable pivots that caused the planetary chaos leading to our current civilization. 00:00 The chance of human existence 00:34 Microbial life 01:42 A series of random events 03:08 The asteroid reset 06:03 The cause of two mass extinctions 07:19 Two big collisions 12:52 The hominid story 15:23 Post-collision

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