When The Nation‘s Naomi Klein traveled to the Gulf of Mexico in December to report on the aftermath of BP’s Deepwater Horizon spill, she saw disturbing signs of the oil’s destruction. But after she left, the research crew aboard the WeatherBird II encountered a slimy substance made up of dead plankton and other organisms coating the ocean floor that none of them had ever seen before. Where did this black goo come from?

Go here to read more about the mystery of the black goo, and be sure to read Klein’s full report from the Gulf, "The Search for BP’s Oil."

Video by Brian Zelinski with thanks to the USF research crew aboard the WeatherBird II.