WASHINGTON -- A giant belch of methane gas from deep under the sea 55 million years ago may have helped mammals take over the world, researchers said Friday.
They said they had found strong evidence of a huge release of the gas -- the fuel behind "natural gas," swamp gas and the belches of cud-chewing animals -- which coincides with a period of dramatic global warming.The idea has been around for a few years, but Miriam Katz, who is earning her doctoral degree in geology at Rutgers University in New Jersey, and colleagues said they found evidence of this methane release in the Atlantic ocean off the coast of Florida.
She said the findings can also help scientists understand global warming today. Carbon dioxide, one of the products of methane, is still a significant contributor to global warming.
"We know that 55.5 million years ago, carbon dioxide was added to the atmosphere at a rate comparable to present-day fossil fuel input, providing the potential to use the past changes in carbon dioxide levels to shed light on future climate change possibilities," Katz said in a statement.
Right about the same time, which was 10 million years after the dinosaurs started dying off, many species of mammals arose.