This beautiful pronghorn buck was taking a late morning siesta in Yellowstone National Park near the north entrance. He was the dominant buck hailing over a herd of nearly 100 strong. The fastest land animal in north America and the 2nd fastest animal in the world next to the cheetah, they are capable of speeds up to 61 MPH. Pronghorns are the only surviving members of their family, Antilocapridae, one of my favorite mammals to photograph.