Arctodus pristinus and Arctodus simus, collectively known as short-faced bears, were massive Pleistocene-era carnivores. Known for their long legs and short snouts, they roamed North America. Arctodus simus, the larger of the two, could reach up to 12 feet standing upright. These bears were likely omnivorous, with a keen sense of smell aiding in foraging across diverse habitats, from open grasslands to forests.

Arctodus pristinus and Arctodus simus are both species of the extinct genus Arctodus, commonly known as the short-faced bear. These species were native to North America. Arctodus simus had a geographical distribution that ranged from Alaska and the Yukon in the north to as far south as California and Mexico. Arctodus pristinus was primarily found in the southeastern United States, including areas such as Florida, Georgia, and South Carolina.

Arctodus pristinus and Arctodus simus inhabited a range of environmental conditions typical of the Pleistocene epoch. These conditions included open grasslands, forested areas, and mixed environments that provided ample space for roaming and hunting. The climate during this period varied from cooler glacial conditions to warmer interglacial periods, which influenced the availability of prey and vegetation.

Both species occupied the ecological niche of apex predators and scavengers. They were highly adapted to a carnivorous diet, preying on large mammals such as horses, bison, and even other bears. Their large size and powerful build allowed them to dominate the food chain, and they likely played a significant role in shaping the Pleistocene ecosystems of North America. Arctodus simus, in particular, is known for being one of the largest terrestrial mammalian carnivores of its time, which influenced its hunting strategies and territorial range.