Ancient Sea Monsters Recently, paleontologists unearthed the fossilized remains of a 35-foot, 240 million-year-old ichthyosaur in Nevada's Augusta Mountains and instantly knew this creature would have been the ocean's top predator. Join the investigation as scientists attempt to understand where this unique creature fits in the evolutionary history of the first sea reptiles. Both in the lab and in the field, paleontologists search for clues to explain how a species that originally came from land transformed over millions of years into a purely aquatic creature.