The muddy plume waters of the Amazon River have been hiding a massive coral reef. You don’t hear a lot of good news about coral reefs these days, so the the discovery of more than 3,600 square miles of undiscovered reef at the mouth of the Amazon River is a pretty big deal. The Atlantic reports researchers in the 1970s caught a few types of fish that indicated a reef might be present along the coast of northeastern Brazil, but it wasn’t taken seriously. The waters at the mouth of the Amazon are some of the muddiest in the world, according to the Guardian. Sediment and other debris from all over South America are rocketed hundreds of miles out to sea, blocking the sunlight believed necessary for MORE