Fatal stegosaur-spike wound seen

They may have been plant-eaters, but stegosaurs were no easy prey: Researchers have found the fossil remains of what might be a deadly wound inflicted by the creature’s spiked tail.

Stegosaur tails have been a matter of some debate. While paleontologists used to say they were only for decoration, recent studies have suggested that the spiked, dexterous tails were actually used in combat. In 2005, researchers reported that a nonfatal wound found in the fossil of an allosaur — a fearsome predator of the stegosaurus’s age — was most likely inflicted by a stegosaur tail.

But it turns out that those tails could do more than just keep predators at bay. They may have been deadly under the right circumstances.

At a meeting of the Geological Society of America on Tuesday, Houston Museum of Natural Science paleontologist Robert Bakker and his colleagues presented evidence that a stegosaur killed an allosaur with some kung-fu-like tail combat.

Limber tail

The fatal stab wound — which most likely caused infection, since Bakker and his team can’t find any signs that it healed — was inflicted by something shaped precisely like a stegosaur tail spike. To hit the allosaur at the proper angle to inflict such a wound, the stegosaur would have had to sweep its tail under the predator and twist it around. Bakker and his team say that, unlike other dinosaurs, stegosaurus had this level of tail dexterity.

“They have no locking joints, even in the tail,” Bakker said in a statement. “The joints of a stegosaur tail look like a monkey’s tail. They were built for 3-dimensional combat.”

The allosaur would have met an unpleasant demise. The wound inflicted by a twisty stegosaur tail would have been similar to those seen in goring accidents during bull runs. Assuming this wasn’t just one dinosaur’s lucky shot, it seems like stegosaurs might have been a force to be reckoned with.