Mosasaurs have long been determined to be apex predators in the Cretateous oceans. But still, there has been questions as to what they ate. But now, from a mosasaur fossil found in 2008 in Alberta, Canada’s Korite International Ammolite Mine, there are some tantalizing clues. It is summarized nicely by Brian Switek in he Phenomena blog over at National Geographic story. The actual specimen is described in a paper in the Journal of Vertabrate Palaeontology.