The flatulence from cows produces enough natural gas today to have a significant impact on global warming. Now imagine what kind of similar impacts dinosaurs might have had 150 million years ago. This is exactly what scientists from Liverpool John Moore’s University, the University of London, and the University of Glasgow set out to discover. During the Mesozoic Era, the Earth was approximately 10 degrees C (18 degrees F) warmer than it is today. Knowing that the flatulence emitted by livestock affects modern climates, scientist David Wilkinson at LJMU led this study to figure out what the gases from much larger prehistoric beasts could do. The scientists estimated the dinosaur output using knowledge of today’s horse output versus their bodymass. The result? Dinosaurs contributed approximately 520 million tons of methane gas every year; that’s 5 to 10 times that produced by all of today’s animals. But these huge beasts can’t get all the credit—the methane actually comes from microbes in the dinos’ digestive tracts. The bigger the beast, the more microbes and the more methane produced. And even though cows are relatively small animals compared to dinosaurs, scientists are still worried about their contribution to global warming today. A 2006 study by the United Nations’ Food and Agricultural Organization reported that livestock flatulence is responsible for more than one third of the world’s methane gas. Researchers are currently looking into diet additives for cows that would reduce their methane output.
Discover more at BBC Nature News.
The journal Current Biology has the published results of this study.
Read the UN study, entitled “Livestock’s Long Shadow – Environmental Issues and Options.”