Paul Matheus, paleontologist at the University of Alaska Fairbanks, determined that Arctodus moved in a pacing motion like a camel, horse, and modern bears, making it built more for endurance than for great speed.[8] A. simus, according to these arguments, was ill-equipped to be an active predator, leading some to conclude that it was a kleptoparasite,[8] using its enormous size to intimidate smaller predators, such as dire wolves, Smilodon, and American lions, from their kills and steal their food