In which John gets curious about the last time global human population declined and ends up learning about a period of human history called The General Crisis.
Thanks to Our World in Data for being such an amazing source of information about life on Earth: https://ourworldindata.org/ And thanks to Hannah Ritchie for answering my question!
Learn more about the general crisis: https://en.wikipedia.org/wiki/The_General_Crisis
Subscribe to our newsletter! http://nerdfighteria.com/newsletter/
And join the community at http://nerdfighteria.com http://effyeahnerdfighters.com
Help transcribe videos – http://nerdfighteria.info
John’s twitter – http://twitter.com/johngreen
John’s tumblr – http://fishingboatproceeds.tumblr.com
Hank’s twitter – http://twitter.com/hankgreen
Hank’s tumblr – http://edwardspoonhands.tumblr.com