Smithsonian scientists have discovered the fossils of a new species of river dolphin that lived more than 5.8 million years ago Named Isthminia panamensis, the ancient mammal might have measured more than nine feet in length. Modern river dolphins have broader flippers than their saltwater cousins, as well as more flexible necks and longer snouts, which help them hunt in silty water. Read more http://www.nbcnews.com/science/environment/ancient-river-dolphin-discovered-n419441
