Videos move very quickly, almost frantically at times, making them more like entertaining overviews of these topics than serious lessons.
There are a couple of innuendos thrown into both videos, so watch them and use your discretion before showing them in your classroom.
In the following video, John Green investigates the agricultural revolution and the dawn of human civilization. How people gave up hunting and gathering to become agriculturalists. How that change has influenced the world we live in today. . Also, there are some jokes about cheeseburgers.