Short Faced Bear - Predator, Scavenger, of Just Plain Terror?

Figure One - Arctodus simus, the giant short-faced bear.  

One of the major themes that I emphasized in my prehistoric adventure book series titled the SHADOW on the TRAIL Pentalogy was that life was onerous and difficult for the First Americans, or Paleoindians, living on the High Plains of North America. They not only had to deal with finding food and water every day, but they also had to contend with natural and manmade disasters such as earthquakes, tornadoes, wildfires, blizzards, droughts, and the hostilities from other humans. It was sure no Garden of Eden. 

One of the bigger challenges that High Plains Paleoindians faced was big and aggressive mammal carnivores. On good days, Paleoindians were at or near the top of the food chain, but I am sure there were days when the human hunters became the hunted. With only their stone-tipped spears and a heartful of courage, Paleoindians faced more than just a few formidable adversaries from the animal kingdom. 

Figure Two - CLICK for the SECOND EDITION

In the second edition of my prehistoric adventure titled CROW and the CAVE, two super mammal predators appeared in my story. I took some liberty in introducing these beasts during the time of the Folsom Complex around 12,600 years ago, even though there is no archaeological evidence that this particular species was still around that late in prehistory. See, it went extinct about that time like many species within the Pleistocene megafauna. Currently, the last recorded occurrence for this species came at the Lubbock Lake site during the Clovis Complex (Johnson 1987:88), some two to three hundred years before my book began. However, I am a realist and believe that as more Paleoindian sites are found and studied, some of these extinct animal species from the Pleistocene might show up in the archaeological record later than anyone expected.  

Below in red is a short passage from CROW and the CAVE that introduces these beasts to you and my book readers:

Hoka hobbled up the ridge, heading westward. Cansha and Heesha caught up to their father. They were not going to wait around to see what happened next. Centuries of combustible material on the cave floor ignited into flames. A short-faced bear, taller than a bison, burst from the cave. The bear stood outside the cave grumbling and peering around in search of whatever disturbed its rest. Smoke from the den billowed upward. The warriors stood paralyzed. A couple of them defecated right there on the spot. None of them had ever seen such a gigantic monster before with huge teeth and long curved claws. Some had heard campfire tales about such a beast but seeing one in person was much more salient than hearing stories.

The gigantic bear glared at the warriors while sniffing the air. It opened its massive jaws and tilted its head to the side. Its yellowish teeth glinted in the bright winter sun. Then, another short-faced bear exploded out of the smoke-filled den and stood alongside the first bear. This bear was smaller, perhaps a yearling or two-year-old, but it was still bigger than several warriors. Its singed fur smoldered in the frosty air. It had been a long winter for the bears. The bears’ appetites had awakened along with their surly dispositions.  

The now-extinct Arctodus simus or short-faced bear was quite a specimen. Based on fossil remains, scientists estimate that Arctodus simus stood a good five and a half feet tall at its shoulders, tall enough to look most Paleoindians straight in the eyes while standing on four legs. The short-faced bear reached ten-foot long and if it stood up on its hind legs like a modern bear species does, a good-sized male stood eleven to twelve feet with a fourteen-foot vertical arm reach. It is estimated that a good-sized male could weigh as much as two thousand pounds. A one-ton bear is nothing to sneeze at. Scientists estimate that male bears were around fifteen percent larger than females. Based on skeletal remains, the size of the short-faced bears seemed to fluctuate with climate, perhaps adhering to Bergmann’s Rule which states that birds and mammals in cold regions are bulkier than individuals of the same species in warm regions.

Figure Three - Not sure if this is accurate to scale, but you get 

an idea of the size of the Arctodus simus. A giant short-faced 

bear was no laughing matter for Paleoindians.   

Arctodus simus or short-faced bears possessed short faces with wide muzzles resembling more of a big cat than a modern bear. Arctodus simus's broad, high vaulted heads differed from narrow-skulled, long-nosed modern bears such as brown and black bears. Based on skeletal remains, Arctodus simus appeared to be fleet of foot. Ursine bears such as brown and black bears are pigeon-toed and tend to waddle back and forth when they walk or run. Arctodus simus walked and ran in a straight line. Scientists estimate that the giant short-faced bear could run anywhere between thirty and forty miles per hour, fast enough to run down most prey, including humans. From this estimated speed, short-faced bears could even run down speedy wild horses and pronghorn over a short stretch of land. 

Arctodus simus was the most powerful predator of the American Pleistocene! (Anderson 1984: 55).  

What did Arctodus simus eat?  

Matheus et al. (2003) studied the oxygen and nitrogen levels in fossil bone collagen for lions, scimitar cats, short-faced bears, wolves, and wolverines in East Beringia, and found that all these predators ate bison, horse, and mammoth, and to a lesser extent caribou and musk ox. The scientists determined that while scimitar cats ate mostly mammoth meat, lions ate mostly bison. The scientists established that although short-faced bears and wolves loved mammoth meat, their diets were quite diverse, and they ate meat from a variety of mammals. Based on their study, the scientists concluded that Arctodus simus was a pure carnivore that scavenged prey mammal carcasses.  

Another analysis on food intake for Arctodus simus came from Wise About Bears (wiseaboutbears.org). They reported that "its [short-faced bear] skull and shearing type of teeth indicate a highly carnivorous way of life. Its eye sockets are set wide apart and face forward, giving it excellent vision. Its short, broad snout had a huge nasal passage, which probably means it had a keen sense of smell and could inhale great volumes of oxygen while pursuing prey. The large width of the jaws in relation to their shortness, plus the huge insertions for biting muscles, gave this bear a vise-like killing bite and the ability to crush bones to obtain marrow. Tests of bone samples show a very high ratio of nitrogen-15 to nitrogen-14, a nitrogen “signature” that indicates a true carnivore. Everything considered paleobiologists conclude that the giant short-faced bear ate only meat."

On the basis of its powerful jaws and humongous teeth, the short-faced bear devoured almost anything it wanted but it appears it was more scavenger than killer, although it probably was proficient at both.

Figure Four - A saber-toothed cat faces off with a short-faced bear over the eating rights
of a horse carcass. The landscape looks like my typical stomping grounds. 
The source of this painting is unknown.   

Arctodus simus was probably quite intimidating to most species, and with its long gait and locomotion capability, the species probably covered a lot of ground. So, what happened to it? Why did it go extinct? At the same time that the short-faced bear and large Pleistocene herbivorous megafauna were struggling to survive, along came more efficient omnivores, the grizzly and brown bears. When the Pleistocene herbivorous megafauna went extinct, it must have heavily influenced the survival of Arctodus simus. 

The fossil record cannot tell us anything about the short-faced bear's temperament. Was it aggressive toward other animals? Humans? Was it moody and cantankerous like grizzly bears or did it have a more tolerant temperament like black bears? One thing is for sure; I would not want to cross paths with a hungry Arctodus simus! When you read CROW and the CAVE, you will understand why.  

Read the entire SHADOWS on the TRAIL Pentalogy series for all my stories.    

    

      

Figure Five - CLICK to ORDER SHADOWS on the TRAIL, the Second Edition

1984    Anderson, Elaine

           Who's Who in the Pleistocene: a Mammalian Bestiary in Quaternary Extinctions - a             Prehistoric Revolution, edited by Paul S. Martin and Richard G. Klein. The                             University of Arizona Press. Tucson. 

1987    Johnson, Eileen.

            Lubbock Lake - Late Quaternary Studies on the Southern High Plains. Texas A & M             University Press. College Station. 

2003    Matheus, P., R.D. Guthrie, and M.L. Kunz. 

                Predator-prey links in Pleistocene East Beringea. Evidence from stable isotopes.                    Third International Mammoth Conference, 2003: Program and Abstracts: 80.                         Occasional Papers in Earth Sciences No. 5. Paleontology Program, Government                     of the Yukon.