Evidence of herd hierarchy is evident very early on in horse’s lives. In the beginning, with very young foals, it is a matter of temperament and genetics over environmental influence. Obviously, the very young have not had any environmental training and lack life experience. However, some newborns exhibit aggressive intentions toward curious investigators, and their genetic personality is revealed. By the time foals are a few months old, they show strong signs of dominance or submission, and pecking orders get established early on among peers. The mother’s disposition and herd ranking influence the foal’s attitude, without a doubt. These learned attitudes carry on into adulthood. Individual dispositions also determine where horses fall into line in the social pecking order of the herd. Size and age rarely matter. Dispositions are formed and altered and sometimes completely changed in herd groups over time. Gentle souls can rise to the occasion of leadership, adapting to changing situations. Dominant horses are first to eat, drink, and establish themselves in shelter situations and herd movements. The social cues of horses are often very subtle, the flick of an ear, the swish of a tail, the raising of a head, all communicate intention, but sometimes outright physical aggression is used. The addition of a new individual to a herd group does not automatically place them at the bottom of the social hierarchy. Authoritative horses quickly master the more submissive personalities then go about the business of challenging the other rulers. The addition or subtraction of just one individual, either dominant or submissive, can change the entire structure among a band of horses. In this image, a weanling filly arrogantly asserts her rank to an incoming herd mate. Her unnecessary crabbiness is evident in his surprised expression. This filly was raised by a clear leader among the mares and has adopted her superior manner, throwing her weight around without due cause, just like a spoiled pre-teen.
