Even though they've been extinct for several million years, farting dinosaurs may have been partly to blame for heating up the planet -- mainly because they ate so damn much, scientists say. The chief culprits, posits Professor Graeme Ruxton of St. Andrews University in Scotland, were 100-foot-long plant-gouging sauropods, which weighed up to 80 tons and had enormous appetites. In fact, Ruxton and his researchers estimate the beasts, over the course of 150 years, collectively produced 520 metric tons of methane, more than all of today's sources put together. It's possible these creatures cooked their own goose with all those flatulent emissions, notes Ruxton. Live by the fart, die by the fart.