Why can't we see evidence of alien life?
2,914,216 views | Chris Anderson • TED-Ed
Stand by for an animated exploration of the famous Fermi Paradox. Given the vast number of planets in the universe, many much older than Earth, why haven't we yet seen obvious signs of alien life? The potential answers to this question are numerous and intriguing, alarming and hopeful. [Directed by Andrew Park, narrated by Chris Anderson].