The big dark stallion in this image towers over most of the other horses on the range. He's very big and powerful, but not very good at keeping a herd of mares. Over the past year, he has won and lost many females. When this photo was taken, he was single again and fighting with the herd stallions in an attempt to win back some females. Although he is very big, he just can't hold his own against the competing males. The little gray stallion with Mooch in this frame faced off with and then chased the bigger stallion away.

My son and I have tried to bet on which horse would prevail in a fight, and we have learned that size takes a back seat to the aggressiveness and confidence of a horse. Many of the small and scrawny stallions are best at fighting and maintaining the right to breed a larger band of females.