I was in Jackson Hole Wyoming where I saw a herd of Bison. I sat in my car using my car as a safe photo blind and photographed the Bison herd. While I was watching, I saw two bulls start challenging each other and locking horns. This photo was shot after they had been at each other for about a minute when the one on the left backed up a few paces and prepared to charge again. This photo was shot right as he started his charge. I love the intense looks in their eyes as they each prepared for impact.