Watch full film: http://www.dailymotion.com/video/x10bwbr_critical-mass_news

Things aren't looking too good for the world's population; as we multiply at an alarming rate there is not enough food, space... or sense. With the planet bursting at the seams the intelligence and physiological traits that make us human are now crucial to mankind's survival. This intelligent film interweaves a fascinating 1960s rat experiment with a slick snapshot of today's urban jungle. As a number of disturbing parallels emerge, you can't help but be affected by this surprising doc.