The Apatosaurus was found in 1877 by a planteologist named Othniel C. Marsh. The name Apatosaurus means “deceptive lizard.” Did you know that the Apatosaurus was a relitive to the diplodocus. It was also desided that the Brontosuarus was the same thing as a Apatosaurus. A full grown Apatosaurus can weigh up to 25 to 40 tons wow! It was about 75 ft. tall. Were the babies were light enough to walk on two feet? By reserch scientist do believe by the foot prints they found were the Apatosaurus feet but on hind legs not all four! Did you knoiw scientist thought before Apatosaurus lived underwater? Well its true! Heres some facts about the Apatosaurus.