Watch Discovery Channel Documentaries online: Episode 41 Valley of the T-Rex

Challenging a century of romantic perceptions, Tyrannosaurus, says Jack Horner, was a nasty-looking, hunched-over beast that was a lousy runner with mediocre vision and had spindly little arms that would have been useless in a fight. But T. rex would have been a masterful scavenger. Horner's colleagues in paleontology seem largely unconvinced.

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