This week on Crash Course Big History, Emily is talking about process of human evolution, and the knack for innovation that has allowed humans to become so dominant on the Earth. Human innovation, and the ability to build on those innovations generation after generation is what makes humans different than other animals. Collective learning is enabled by our highly evolved and efficient ability to communicate with each other and pass on information. With great power, of course, comes great responsibility, and how we use this powerful tool has kind of a mixed track record.

• John Green
• Hank Green