Yellowstone National Park, Wyoming
1997
Joel Sartore

Bison dot a Yellowstone snowscape, some sweeping the drifts aside with their heads to uncover vegetation. A thick mantle of hair over their forequarters and heads and a heavy coat over their hindquarters allow bison to keep warm in harsh winter temperatures.

(Photograph shot on assignment for, but not published in, "Return of the Gray Wolf," May 1998, National Geographic magazine)

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