Like others of their kind, sable antelope have a social structure based on territory, age, and strength. The strongest adult males, called “bulls,” set up territories in good grazing areas. They constantly patrol, encouraging females to enter and challenging other males. A challenge begins with circling each other, pawing the ground and lashing tails. It ends when the bulls drop to their knees and lock horns. From there it's a pushing contest, and the strongest antelope wins.