Horses playing - ranking and intelligence - and lust of a stallion

Many people still think that Horses are having a continues fight over dominance, that is hum a trait and nonsense. Horse do have a ranking but they develop slow and the ranking changes without fights but only by developing skills. If they would fight over dominance all the time then in winter many would die because they waste to much energy. Ranking is not about dominating anybody, actually the one who is high in ranking does not fight at all but is smart and has a way to avoid fights. Thats intelligence