Follow us on FacebookFollow us on TwitterFollow us on FlickrFollow us on YouTubeFollow us on PinterestFollow us on Instagram
Home > Research & Collections > News > California Short-Faced Bears Had a Sweet Tooth

California Short-Faced Bears Had a Sweet Tooth

How these bears adjusted their diet

Short-faced bears (Arctodus simus) were the biggest predators in L.A. during the Ice Age. Illustration © Mary Butler, NHMLA.


There weren’t any dentists around L.A. during the Ice Age, but if there had been, they would have had some short-faced bears in the waiting room. A recent study found that these bears had a surprising number of cavities in their teeth, and it’s making us rethink the probable diet of this ancient extinct bear.

Short-faced bears are one of the many predators we find in the La Brea Tar Pits that lived during the Ice Age, between about 50,000 to 10,000 years ago. With the males weighing as much as 1,800 pounds, they were the biggest carnivore around at the time (while Columbian mammoths were the biggest herbivore).

Scientists have long thought that these short-faced bears were strict carnivores, but this new study calls that into question. Researchers discovered that 15% of the studied short-faced bear fossils from the La Brea Tar Pits had tooth decay, so it’s likely these animals were eating more than just meat. They might have dined on sweets like juniper berries, which have also been preserved in the tar pits. And without toothbrushes (or the desire to use them), their teeth paid the price of these bears’ sugar fix.

a photo of a man leaning over the skull of a short-faced bear, placing putty over its teeth
Postdoctoral researcher Francisco Serrano makes a mold of the fossilized teeth of a short-faced bear to study the microstructure of the dental cavities. Photo by La Brea Tar Pits Collections Manager Aisling Farrell.

But was this true for short-faced bears elsewhere? This species of bear lived throughout western North America during the Ice Age, and when scientists studied short-faced bear fossils from Alaska and Yukon, they didn’t find signs of decay in their fossilized teeth. Why didn’t they have the same evidence of a sweet tooth?

The short-faced bears in the Pacific Northwest may have had easier access to meat because there were few predators in the area at the time. In comparison, the ecosystem by the La Brea Tar Pits included many different species of hunters — saber-toothed cats, American lions, dire wolves, coyotes, and more — and along with them, much steeper competition for each meaty meal. So while short-faced bears in L.A. expanded their diet to include sugars like berries to survive, short-faced bears in Alaska kept to a strict carnivorous diet and didn’t develop the same tooth decay.

It’s just a shame short-faced bears in L.A. went extinct before they could try frozen yogurt.


Want to get updates for the R&C News sent to your email ?

Sign up below, and we'll send you the latest!