Herds of sauropods may have caused large scale climate change during their time. Producing enough methane gas from their ruminant style digestion, to intensify the greenhouse effect, according to new research just published in Current Biology.
The Sauropods, known for their enormous size and giraffe like necks, were spread across the globe 150 million years ago. Like cows and other modern ruminants, they digest their food by fermenting it in their stomachs with the help of microbes. This allows them to digest food that other animals can’t.
“A simple mathematical model suggests that the microbes living in sauropod dinosaurs may have produced enough methane to have an important effect on the Mesozoic climate,” said Dave Wilkinson of Liverpool John Moores University. “Indeed, our calculations suggest that these dinosaurs could have produced more methane than all modern sources — both natural and man-made — put together.”
The research started by noting the large methane emissions from domesticated cows. Emissions from cows contribute in a significant way to climate change. Sauropods were considerably larger, and were a very widespread successful species, covering nearly the whole earth.
Methane expert Euan Nisbet at the University of London helped to work out the numbers.
“Clearly, trying to estimate this for animals that are unlike anything living has to be a bit of an educated guess,” Wilkinson said.
Methane production in modern animals has been extensively studied, well enough that emissions from animals of different sizes can be accurately estimated. Apparently all you really need to know is the mass of the animal.
Just one medium sized sauropod weighed nearly two metric tons, and could live in very large groups.
The research calculated that global yearly methane emissions just from sauropods would have been around 520 million tons, comparable to modern yearly methane emissions from all sources. For a comparison, modern ruminant animals produce 50-100 million tons a year, and a large portion of that is from the massive numbers of domesticated farm animals.
The study authors said this should serve as a reminder of the importance and impact methane has on the planets climate.