Blood tests indicate that the buffalo roaming Wind Cave National Park and Yellowstone National Park are the only two public herds in the U.S. that lack evidence of cattle genes. “It’s the closest thing to what used to wander the prairies for thousands of years,” said Tom Farrell, chief of interpretation for Wind Cave National Park. “This is the closest in going back in time and seeing what the Great American Desert was like.”(via Oh Ranger)