Researchers from the Hungarian Natural History Museum
and University of Alberta
have discovered fossils that they believe represent the world's first real river monster -- a never-before-identified breed of mosasaur that thrived in fresh water rather than open ocean.
The specimens represent the first evidence of mosasaurs
-- initially land-dwelling reptiles that returned to the sea like modern dolphins and whales -- who left their ocean habitats in favor of freshwater homes like rivers
, developing adaptations that would have let them thrive in the new environments where they were likely to top of the food chain.