Valley of The T-Rex - Plot

Plot

The program shows Horner and his digging team as they travel to the Hell Creek Formation in Montana, USA, 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:

• Forelimbs: Tyrannosaurus short forelimbs seems like they could not hold on to struggling prey. Horner argue that predators have well developed forelimbs with claws to hold prey down while the jaws do the killing, while Tyrannosaurus could not use its forelimbs for much more than to "Scratch it's belly". Horner believes the upper arm of Tyrannosaurus would have been embedded in muscle, and not externally visible in life. And if Tyrannosaurus stumbled and fell while trying to run, the small forelimbs would not be enough to brake the fall, and it would get fatal injures.
• Speed: Horner argues that Tyrannosaurus must have been too slow to chase down prey, and also points out that some specimens of Tyrannosaurus have longer thighbones than shinbones. According to Horner, this is not the case in fast-running animals like Saurornitholestes, which have longer shinbones than thighbones.
• Brain and senses: Horner suggest that Tyrannosaurus had a poorly developed sense of sight, and would not be a good predator. On the other hand, the huge olfactory bulb indicates "a tremendous sense of smell", used to find carcasses.
• Jaws and teeth: Tyrannosaurus had powerful jaws and robust teeth. Horner argue that Tyrannosaurus used them for crushing bones, as modern scavengers like hyenas do to feed on marrow when the flesh of carcass has rotted away. Predators teeth are normally thin and sharp for slicing flesh.

Tyrannosaurus becomes depicted as Horner imagines it: a big, slow-moving animal, traveling across the landscape in search of carcass. Horner thinks Tyrannosaurus would have a repulsive look: dark body and a red head, and would give off a terrible odor. This would help it discourage other meateaters, like dromaeosaurs, from carcasses.