Reeve's Bonebed is known for the recovery of casts of the brain cavity (
endocast) of oreodonts. When an animal dies and the soft tissues decay, sediments fill the orifices of the bones including the
brain case inside the
skull. If the bone subsequently falls apart, a cast of the inside of the skull may remain intact. Hundreds of brain casts, mainly from
Bathygenys, were recovered from Reeve's Bonebed. These casts have been used to gauge the size of the brain of these animals, as well as the size of the various brain lobes. The physical arrangement of the brain can give clues about the life of the living animal, such as how important smell was to it, as used in CT scans of
Tyrannosaurus. Studies involving more than 150 of these endocasts have been performed from the Reeve's Bonebed samples. ==References==