Albertosaurus older "Gorgosaurus libratus" (sometimes called "Albertosaurus libratus"; see below). These two species are the only described albertosaurines; other undescribed species may exist. Thomas Holtz found "Appalachiosaurus" to be an albertosaurine in 2004, but his more recent unpublished work locates it just outside Tyrannosauridae, in agreement with other authors. The other major subfamily of tyrannosaurids is the Tyrannosaurinae, which includes "Daspletosaurus", "Tarbosaurus" and "Tyrannosaurus". Compared with these robust tyrannosaurines, albertosaurines had slender builds, with proportionately smaller skulls and longer bones of the lower leg (tibia) and feet (metatarsals and phalanges). Below is the cladogram of the Tyrannosauridae based on the phylogenetic
Halving the Bones years prior to the events depicted in the documentary. In Japan, when someone is cremated, their bones are not reduced to ash. Instead, half are preserved and split between the descendants. The rest of the bones are buried in a cemetery. Ruth is given a fragment of skull, a small part of a rib, and an unidentified bone to bring back the United States for her mother who did not attend the funeral. Reluctant to give the bones to her mother, Ruth lets the bones sit in a tea can on her shelf in her closet. Years pass by, and