In the pantheon of predators, it's one of the greatest discoveries since the T-Rex: a snake 48 feet long, weighing in at 2,500 pounds. Uncovered from a treasure trove of fossils in a Colombian coal mine, this serpent is revealing a lost world of giant creatures. Travel back to the period following the extinction of dinosaurs and encounter this monster predator (http://www.smithsonianchannel.com).