More than a quarter of the world’s human-related methane emissions come from livestock burps and farts, which is bad enough — but imagine what the climate would look like if cows weighed 25 tons. Back in dinosaur days, we had some seriously outsize herbivores roaming the planet, making some seriously outsize butt music. A team of British researchers has now calculated how much gas those giant asses would have passed, and concluded that dinosaur emissions contributed significantly to Mesozoic global warming.
Based on the relative size and gassiness of cows, the researchers figure that sauropods — giant herbivorous dinosaurs like the Apatosaurus — would have put out more than 570 million tons of methane in a year, more than current methane emissions from human and natural sources combined. That would help account for the fact that the Mesozoic climate was up to 18 degrees F warmer. It was probably smellier as well.
Dinosaur gases 'warmed the Earth', BBC.