The "bulldog bear" was the largest land carnivore in North America during the Pleistocene epoch. Standing five feet tall at the shoulder, it could have reached 11 feet when up on its hind legs and could have weighed up to1500 pounds. This bear was taller, leaner, and more rangy in build compared to present day Kodiak bears. But Arctodus was larger overall, swifter and more lethal.
Short faced bears of the genus Arctodus ranged from both coasts of North and South America. Today, the only living descendant of these powerful predators lives on in the Andes foothills in the form of the shy, forest- dwelling Spectacled Bear, which also has a short, broad snout. The remains of the largest Arctodus have been found in Alaska and the Canadian Yukon, these are given the sub-species name yukonensis, which is the species I have depicted here.
The unusual skull of Arctodus exhibits features that point to a highly predatory way of life. The skull's overall shape and dentition is reminiscent of a lion's, with large canine teeth and specialized, carnassial (flesh- shearing) molars. Arctodus had a characteristic short muzzle with no discernable forehead; the eye sockets were set wide apart and face forward and must have given Arctodus excellent vision. The opening of the nasal passage was huge, and points towards a keen sense of smell, and to the need to inhale great volumes of oxygen, probably during pursuit of prey. The large width of the jaws in relation to their shortness, plus the huge insertions for the pre-masseter, masseter and temporalis muscles gave this bear a vise-like killing bite.
Arctodus was exceptionally long legged, and unlike modern bears, the toe bones of Arctodus articulate straight out in front so they were not pigeon-toed. This gave Arctodus a fast purposeful gait, and an increased ability to run down prey. This is a common physical characteristic of purely carnivorous animals such as lions, or wolves.
Like so much of the Pleistocene megafauna, the record of the short-faced
bear stops at end of the last ice age around 10,000 years ago