It has been estimated that a bite from a grizzly bear can crush a bowling ball.
A Grizzly Bear's Bite Can Crush a Bowling Ball
Picture a grizzly bear clamping down on a standard bowling ball. That 15-pound sphere of polyester resin, engineered to withstand repeated slams against hardwood lanes, would crack like an egg. It sounds like the stuff of tall tales, but the physics checks out: a grizzly's bite force reaches approximately 1,160 to 1,200 pounds per square inch (PSI), comfortably exceeding the 975-1,100 PSI compressive strength of a bowling ball.
Scientists estimate bite force through a combination of direct measurements (using bite force transducers on sedated animals), computer modeling, and skull morphology analysis. The grizzly's massive jaw muscles, particularly the temporalis and masseter, attach to a broad skull with exceptional leverage. When those jaws slam shut, they generate crushing power that serves a very practical purpose in the wild.
Why Such Devastating Force?
Grizzlies aren't crushing bowling balls in nature—they're processing a wildly varied diet that demands versatility. Their jaws need to crack open nuts, crush bones to access marrow, tear through tough vegetation, and subdue prey ranging from salmon to elk. That 1,200 PSI bite isn't just for show; it's an essential tool for survival.
The skull structure tells the story. A grizzly's broad, robust head houses attachment points for enormous jaw muscles. The sagittal crest—that ridge running down the center of the skull—provides extra surface area for muscle attachment. Combined with teeth designed for both shearing and crushing, the result is a jaw that can adapt to whatever food source the bear encounters.
How Does It Compare?
Context makes the numbers even more impressive:
- Human bite force: 150-200 PSI (enough for our omnivorous diet, pathetic by comparison)
- Lions: Around 650 PSI (powerful, but specialized for meat)
- Tigers: Approximately 1,050 PSI (getting closer)
- Grizzly bears: 1,160-1,200 PSI
- Polar bears: 1,200-1,300 PSI (the heavyweight champion among bears)
For reference, the pressure required to crush a human femur—the strongest bone in the body—is roughly 1,700 PSI. A grizzly can't quite manage that, but they can certainly crush smaller bones with ease.
The Bowling Ball Test
While no research team has strapped a grizzly bear into a bowling alley for science (sadly), the engineering is straightforward. Bowling balls are manufactured with compressive strength ratings because they need to survive high-impact collisions. A standard ball can withstand roughly 975-1,100 PSI before the material fails and cracks form.
A grizzly's bite exceeds that threshold. The bear's canines would likely puncture first, creating stress fractures that propagate through the ball. Given sustained pressure—and grizzlies can maintain their bite—the ball would eventually fracture. It wouldn't explode dramatically, but it would fail structurally, which counts as "crushed" in our book.
Don't Test This at Home
The practical takeaway? If you encounter a grizzly in the wild, remember that those jaws can crush your skull significantly easier than a bowling ball. Their bite force is an evolutionary masterpiece—a tool honed over millennia to make them one of North America's most formidable apex predators. Respect the PSI, respect the bear, and keep your distance.