Valley of the T. rex
Valley of the T. rex is a Discovery Channel documentary, featuring paleontologist Jack Horner, that aired on September 10, 2001. The program shows Horner with his digging team as they travel to Hell Creek Formation in search for dinosaur fossils, while also following Horner as he presents his view of the theropod dinosaur "Tyrannosaurus rex" as a scavenger rather than a predator, as it is often portrayed in popular culture. Plot. The program shows Horner and his digging team as they travel to the Hell Creek Formation in Montana, United States, and dig up dinosaurs . The program also follows Horner as he presents arguments for his case of "Tyrannosaurus" as a scavenger. Horner argues that there is not the slightest evidence that "Tyrannosaurus" hunted its own prey. Instead, Horner believe the evidence should be clear that "Tyrannosaurus" was a scavenger, lamenting that "no one likes that idea". Some of Horner's arguments for a scavenger-only "Tyrannosaurus" are: "Tyrannosaurus" becomes depicted as Horner imagines it: a big, slow-moving animal, traveling across the landscape in search of a carcass. Horner thinks "Tyrannosaurus" would have a repulsive look: A dark body, a red head, and it  would give off a terrible smell. This would help it frighten away other meateaters, like dromaeosaurs, from carcasses. His description of T. rex is "big, nasty, and stinky." Criticism. Since "Valley of the T. rex" was shown on television, it has been met by criticism. Many of the arguments Horner use to support his case have been examined by other paleontologists, who do not agree that they conclusively show "Tyrannosaurus" was an obligate scavenger. As for "Tyrannosaurus" short forelimbs, it has been pointed out that predators like wolves and hyenas do not use their front legs to take down prey . Moreover, hyenas, like "Tyrannosaurus", have jaws and teeth to crush bone, yet they use it to hunt their own prey. In the program, Horner measure the leg bones of MOR 1128, or "G-rex", one of the skeletons which were shown in the program as it was dug up. The narrator says that "G-rex" was found in a rock layer 90 meters below where "Wankelrex" was found, and Horner says "G-rex" are thought to be 3 million years older than other known specimens (like "Wankelrex"). Horner also says that "G-rex" have thighbone and shinbone of equal length , while "Wankelrex", have longer thighbone than shinbone. Horner argue it is an indication that "Tyrannosaurus" over time lost the ability to run and evolved to more specialization as a walking scavenger. It has been argued by Garner, however, that the shinbone of "Wankelrex" are restored from broken fragments, making it inappropriate as reference in comparative morphology. Also, according to other reports, "G-rex" also have longer thighbone (1.26 meters) than shinbone (1.12 meters). Holtz also points out that longer thighbones than shinbones is a condition also found in horses, which are fast running animals. A shorter shinbone might be compensated  by a relatively long metatarsus, which is seen both in horses and tyrannosaurids. Other scientists have argued that "Tyrannosaurus" could have had a well-developed sense of sight with binocular vision, typical of a predator, and a well-developed sense of smell in "Tyrannosaurus" could have been used for hunting, rather than just finding carcasses. Evidences for a predatory lifestyle in "Tyrannosaurus" includes discoveries of skeletons from herbivorous dinosaurs like "Edmontosaurus" and "Triceratops", with evidence of healed bitemarks on them, indicating they survived attacks from big predators, possibly "Tyrannosaurus".