Driven by instinct at a very early age, two twenty month old males begin to hone the skills necessary to eventually become a dominant stallion with a herd of mares. Not all stallions reach this status, or lose that position because they lack the aggression and strength to keep it.
I have been watching the youngster on the left since he was born. Has shown remarkable confidence and lack of fear. He would be my bet to become the highest ranking stallion by the time he reaches the age of about six.