Great video Lex. I tend to agree with your estimates on most of the parameters, but the big unknown to me really is the manifestation of intelligence from life. The dinosaurs had 100m years on the planet without any evidence of intelligence emerging (although that's not to say it didn't). If that asteroid hadn't hit earth 65m years ago, would Earth be just another planet with life but no intelligence? <br><br>Also I like how the Soviet Union even got a mention in this video. :)