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
Knowing and the Known with animals and plants, as well as objects of all types, in any environment. Men and women have, are, and will present their acts of knowing and known in language. Generic people, and specific men and women, are known to be vulnerable to error. Consequently, all knowledge (knowing and known) whether commonsensical or scientific; past, present, or future; is subject to further inquiry, examination, review, and revision. Knowing and the Known Knowing and the Known is a 1949 book by John Dewey and Arthur Bentley. As well as a Preface, an Introduction and an Index, the book consists of 12