valley of the t. rex

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Killing a Legend: New Evidence Paints T. Rex as a Nasty Scavenger, Not a Vicious Hunter

By Robert Locke, Dinosaur Magazine

Tyrannosaurus rex was 40 feet (12 meters) long, weighed in at 6 tons and stood 15 feet (4.5 meters) high. Enormous, powerful legs could have stepped over a car in a single stride. Four-foot (1.2-meter) jaws, raggedly studded with 7-inch (17.8-centimeter) teeth could crush bone and consume 500 pounds (225 kilograms) in a single bite. Clearly this was the ultimate predator — the undisputed master of its Cretaceous world. Every living thing must have trembled when the "tyrant lizard king" was on the prowl.

Or not. One of the world's top paleontologists says T. rex was not a hunter at all. The fiercest giant of dinosaur lore was but a well-designed scavenger that had much more in common with buzzards and hyenas than with lions and tigers.

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. Even worse, if T. rex tripped and fell or was toppled by a stubborn foe, those arms could do little to dampen the impact of tons of falling dinosaur; the all-but-inevitable broken bones could easily prove fatal.

But T. rex would have been a masterful scavenger. Huge olfactory gear could have smelled a carcass from miles away, and legs designed for walking — not running — could cover vast distances in search of carrion, much as olfactory-gifted vultures soar over the landscape for hours. And those vicious teeth were adept not at slicing through choice cuts of meat but at crushing the bones and cartilage left behind by the true hunters.

Challenging a century of romantic perceptions — and widely held scientific conclusions — is hardly a popular chore. The killer T. rex, greatly beloved by children and filmmakers, is memorialized in models, movies, lesson plans and countless museum displays. Horner says the reaction to his hypothesis is often heated. His colleagues in paleontology seem largely unconvinced.