For a brief period after the dinosaurs vanished, truly gigantic reptiles like the 50-foot snake Titanoboa and twenty-foot crocodiles dominated the swamps of ancient Colombia. Now we've discovered another, much gentler giant - the humongous 60-million-year-old "coal turtle."
Somehow, the Smithsonian Channel has beaten Syfy at its own monster fighting game. They've pit the mighty Tyrannosaurus Rex against the gigantic snake Titanoboa in a prehistoric grudge match, animated the possible outcomes for each carnivorous side.
Sixty million years ago, the world belonged to Titanoboa, a gigantic snake that measured 40 to 50 feet long and weighed over 2,500 pounds. Only one creature could challenge it: a newly discovered, twenty-foot freshwater crocodile.
Paleontologists have discovered fossil remains of the world's biggest snake, which was 13 meters long (over twice as big as this giant anaconda, pictured). Though they lived 60 million years ago, such snakes could re-evolve.