In the aftermath of the Deepwater Horizon disaster in the Gulf of Mexico, scientists embarked on a research cruise with an urgent mission: determining the fate and impact of hydrocarbon gases escaping from a deep-water oil spill. What they found was surprising: Three specific hydrocarbon gases -- ethane, propane and butane -- were responsible for most of the respiration and oxygen loss observed in the deep plumes. They further identified the dominant bacteria present in the plumes and suggested some of the organisms were targeting the natural gases....