Apatosaurus "Apatosaurus" may have been more solitary than other Morrison Formation dinosaurs. Fossils of the genus have only been found in the upper levels of the formation. Those of "Apatosaurus ajax" are known exclusively from the upper Brushy Basin Member, about 152–151 mya. "A.louisae" fossils are rare, known only from one site in the upper Brushy Basin Member; they date to the late Kimmeridgian stage, about 151mya. Additional "Apatosaurus" remains are known from similarly aged or slightly younger rocks, but they have not been identified as any particular species, and thus may instead belong to "Brontosaurus". The Morrison Formation records a
Wyoming Dinosaur Center on the property is from the "Something Interesting" or SI excavation site. This site presents the rare occurrence of both dinosaur trace fossils and body fossils including footprints of many Sauropods and "Allosaurus" as well as skeletal remains from "Camarasaurus, Diplodocus," and "Apatosaurus" - three of the sauropods most common in the area during the Late Jurassic. Most of the bones belong to a juvenile (30 foot long) "Camarasaurus" that was scavenged by many "Allosaurs". This is known based on the presence of both teeth and claw marks on many of the bones present as well as an abundance of