Like cars, some microbes use oil as fuel. Such microorganisms are a big reason why BP's 2010 oil spill in the Gulf of Mexico was not far worse.

 

"The microbes did a spectacular job of eating a lot of the natural gas," says biogeochemist Chris Reddy of the Woods Hole Oceanographic Institution. The relatively small hydrocarbon molecules in natural gas are the easiest for microorganisms to eat. "The rate and capacity is a mind-boggling testament to microbes," he adds.