Where does the grizzly bear come from? According to stories once told by natives of the Pacific Northwest, the grizzly bear was forged by the Great Spirit, who begot the animals of the world from his walking stick. With the heavy end of his staff, the Great Spirit sired a mighty beast to rule the others. It was so powerful and contentious that it chased its maker to the top of the world. This direful creature was the primordial grizzly bear.

Scientists tell a different story, one that begins in the treetops of Asia some 34 million years ago. There appeared the earliest ancestor of the bears, Cephalogale. This dog-sized predator gave way to the "dawn bear," a small, arboreal hunter with teeth designed for grinding vegetation.

A more grizzly-like bear appeared in Europe some 5 million years ago. Called the Etruscan bear, it's the earliest known member of the genus Ursus, a group that includes the grizzly. Its teeth were large and flat, which indicates that it relied rather heavily on vegetation despite being a carnivore.

Around 1.3 million years ago, the brown bear, Ursus arctos, appeared in China. A successful opportunist, it spread quickly across the continent into Europe and northern Africa. It reached the Americas during one of the early ice ages, traveling across the Bering Land Bridge at least 200,000 years ago. Back then, the short-faced bear — the largest bear that ever lived — roamed the continent. It and many other bear species went extinct shortly after the brown bear arrived.

Over time, America's brown bear developed characteristics of its own, like long, white-tipped guard hairs, as seen in certain regions of North America. Whether grizzled, gold or mahogany, America's brown bears are collectively known as the grizzly bear, or Ursus arctos horribilis. The exception is the Kodiak bear, which has lived in isolation on Alaska's Kodiak Island for thousands of years.