The Dire Wolf (Canis dirus) and the Saber-Toothed Tiger (Smilodon fatalis) are two of the most well-known megafauna mammals of the late Pleistocene epoch, prowling the plains of North America until the last Ice Age (and the advent of modern humans). Thousands of Canis dirus and Smilodon fatalis skeletons have been dredged up from the La Brea Tar Pits in Los Angeles, indicating that these two predators lived in close proximity. The question is, which would come out on top in hand-to-hand (or, rather, paw-to-paw) combat? (Be sure to register your opinion about the prospective winner, and see more dinosaur death duels.)
In the Near Corner - Canis dirus, the Dire Wolf
To some people, the Dire Wolf is most familiar as the subject of a Grateful Dead song. To connoisseurs of prehistoric life, though, Canis dirus was the plus-sized predecessor of the modern dog as well as a close relative of the Grey Wolf (Canis lupus), a shaggy, hundred-pound carnivore that scoured the plains of Pleistocene North America as efficiently as Piranhas scour the Amazon basin. (The word "dire," by the way, meaning "fearful" or "threatening," is derived from the Greek word "dirus.")
Advantages. As genus Canis goes, the Dire Wolf was pretty big: some individuals may have weighed as much as 200 pounds, though 100 to 150 pounds was more the norm. This predator was equipped with powerful, bone-crushing jaws and teeth, which it used mostly for scavenging rather than active hunting. Most significantly, the discovery of huge numbers of associated Dire Wolf fossils is evidence of pack behavior; this mammal seems to have been every bit as social as modern hyenas and wild dogs.
Disadvantages. The Dire Wolf had a significantly smaller brain than the Grey Wolf, which may explain how this latter Canis genus helped drive it to extinction. Also, the legs of Canis dirus were much shorter and stubbier than those of modern wolves or large dogs, meaning it was probably unable to run much faster than a house cat. Finally, the Dire Wolf's predilection for scavenging rather than hunting would almost certainly have put it at a disadvantage when faced with a hungry (and irritated) Saber-Toothed Tiger.
In the Far Corner - Smilodon fatalis, the Saber-Toothed Tiger
Despite its popular name, the Saber-Toothed Tiger wasn't actually a tiger; in fact, this prehistoric cat was only distantly related to modern tigers, lions and cheetahs. Of the three species of Saber-Toothed Tiger--the smaller Smilodon gracilis and the larger Smilodon populator were the other two--Smilodon fatalis was the one that dominated North (and eventually South) America. And yes, in case you were wondering, the Greek name Smilodon roughly translates as "saber tooth."
Advantages. The most notable weapons wielded by the Saber-Toothed Tiger were, well, its long, curved, saber-like teeth. However, Smilodon fatalis didn't attack prey head-on with these formidable choppers; rather, it lounged in the low branches of trees, then pounced suddenly from above and dug its enormous canines deep into its victim's flesh. As with the Dire Wolf, some paleontologists believe that the Saber-Toothed Tiger hunted in packs, though the evidence for this is much less compelling.
Disadvantages. As big cats go, Smilodon fatalis was relatively slow, stocky and thick-limbed, with the biggest adults weighing in the neighborhood of 300 to 400 pounds (but nowhere near as nimble as a comparably sized lion or tiger). Also, as scary as its canines were, the Saber-Toothed Tiger's bite was relatively weak; after all, chomping down too hard on its prey might have caused one or both of its saber teeth to break off, effectively dooming that unfortunate individual to slow starvation.
In normal circumstances, a full-grown Saber-Toothed Tiger wouldn't have come within a hundred yards of a comparably sized Dire Wolf. Let's imagine, then, that both of these predators have converged on the La Brea Tar Pits, hoping to snack on an unfortunate herbivore (let's say a Megalonyx) half-submerged in the ooze. Smilodon fatalis is at a disadvantage, because it can't pounce on the Dire Wolf from a tree branch; the Dire Wolf is at a disadvantage, because (all things being equal) it would rather feast on an already-dead herbivore than a hungry carnivore. The two animals dance around each other, the Dire Wolf swatting half-heartedly with its paws, and the Saber-Toothed Tiger lunging (but not very convincingly) with its teeth. Disappointed by the lack of action, the crowd of plant-eating spectators starts to boo (or moo, if you prefer).
And the Winner Is...
The Dire Wolf! It's a good bet that, if Smilodon fatalis roamed in packs, these packs were rather small and loosely associated--whereas the pack instincts of modern dogs and hyenas are much more robust. Sensing that one of the pack is in trouble, and that a change of menu might be in the offing, three or four other Dire Wolves rush to the scene of the fight and swarm over the nonplussed Saber-Toothed Tiger, inflicting deep bite wounds with their massive jaws. Smilodon fatalis puts up a good fight, even breaking one of its teeth in the process, but it's no match for a thousand pounds' worth of hungry canine. A crushing bite to Smilodon's neck ends the battle, and the victorious wolves ignore the drowning herd of giant ground sloths in favor of a more exotic meal.