As Miohippus made the move from forests to grasslands (Table 4.2), the need to band in herds for protection came to be crucial. It was this lifestyle change that spurred the sophistication of the horse’s social structure. The horse engages in a variety of social behaviors as explained by George Waring in his 1982 book.
The social organization of horse groups varies depending on what horses are available in any given environment. The typical reproductive band consists of a group of females, their offspring and at least one stallion. Small non-reproductive groups of bachelor males often form bands; these tend to be unstable as solitary males often leave and join the group throughout the year. Another non-reproductive group consists of non-breeding juveniles or “sub-adults” (Waring, 1982, 142). While solitary horses are hard to find, juvenile horses individually disperse from their maternal band between the ages of three to four. Solitary females often join established reproductive bands without much upheaval while solitary males find this more difficult and often attempt to form their own band (Waring, 1982). These conditions have been observed in feral groups of horses along with remaining Przewalski’s horses (Figure 4.4) and can be used as a reference from which to plan a farm’s turn-out program. In man-made situations when a dominant stallion is often absent, an alpha female often takes over the stallion’s role to herd, protect and lead the band.
A social organization is held together by the bonds and relationships each horse makes with other horses of its group. These social attachments are formed on the basis of age, sex, reproductive status, health and stability of the social group. There are several types of social attachments normally seen in wild or feral herds. A mare and foal form an intimate attachment soon after birth during a process known as “imprinting” (Miller, 2004). Robert Miller developed a foal training technique in the early 1990’s mimicking the imprinting process mares use; it has gained considerable respect in recent years among horse breeders. The process involves spending considerable time touching and rubbing the foal after birth so that it bonds not only with its mother, but with its human companions as well. Imprinted foals are reported to be easier to handle and train as they age than horses that were not imprinted as foals (Miller, 2004).
Other social attachments are formed between young peers, such as siblings or similarly aged foals. Peer attachments are usually marked by alternating periods of play and mutual grooming; these relationships may or may not continue into adulthood (Waring, 1982). Adult peer attachments among males often remain weak, which explains why bachelor groups tend to be unstable. However, mares may form close, long-lasting peer attachments with other mares within their relatively stable band. Aside from the mare-foal attachments, stallions often attach to the foals within the band. Stallions protect foals and mares, taking time to retrieve foals which have wandered from the group if the mare fails to take that initiative. A stallion typically avoids any type of sexual attachment with its own offspring. Instead, he will drive colts and fillies away from the band once they reach sexual maturity (Waring, 1982). Attachments between horses and other species are uncommon, but not unheard of in situations when a foal is raised in isolation. Interspecies attachments involving goats, chickens or dogs are most commonly seen among racing Thoroughbreds or Standardbreds which are often deprived of natural social environments.
Establishing and maintaining social dominance is of utmost importance to the survival and stability of a social group. Social rank tends to approximate a “linear hierarchy” (Waring, 1982, 167); the first individual, the alpha, is dominant over all others and the last individual, the omega, is submissive to all others. Dominance is established through violence, threats of violence, or avoidance, whereas submissiveness is offered by “tooth-clamping” (Waring, 1982, 172) and lowering of the head. The most obvious displays of dominance and submissiveness in domestic horses occur at feeding time; observation of feeding can help owners determine social rank of their horses. Those high-ranking horses begin eating before others and travel the pasture, supplanting submissive horses from their feed troughs for a few moments before moving to the next trough. In this way, the alpha horse eats from every trough while the omega horse may never get to eat at all. The factors that influence social rank are age, sex, size and physical condition. Based solely on age and sex, social rank is as follows: stallion, mare, gelding (neutered male), male juvenile, female juvenile, male foal, female foal (Waring, 1982, 170). Body size and physical condition factors determine whether an established dominant stallion will maintain or surrender leadership. However, individual personality and temperament may be the prime factor determining rank when a dominant horse is challenged. “Aggressive and persistent horses, regardless of weight, height, sex, or length of residence in a band achieve higher ranks than more passive individuals” (Waring, 1982, 171).
Of all the natural instincts inherent in the equine mind, the “flight-or-fight” instinct is perhaps the most important to understanding how to keep and train horses. The first stage in the “fight-or-flight” response is “alert” (Waring, 1982). If a new sound, movement, or approaching vibration occurs, a grazing horse with become alert and attempt to ascertain the source of the stimulus. The horse will cease walking and chewing and raise the head to see, hear and smell better until the source as been identified. Surrounding horses will mimic this behavior. If the stimulus appears non-threatening or is moving away, the horses will resume normal grazing behavior. However, if the stimulus grows stronger or is approaching, the horse will continue to the next stage, “alarm” (Waring, 1982). The horse may vocalize or blow air through the nostrils to draw other horses near. The lead horse, if still at a safe distance, may approach the stimulus momentarily to investigate. If threatened, the lead horse will turn and flee. All surrounding horses, seeing a fleeing companion, will join the flight, whether they had been alerted to the stimulus or not. “Flight occurs with a speed, manner, and distance relative to the stimulus and situation” (Waring, 1982, 177). Simple avoidance of a threat occurs at a walk, while a pursued horse will commence flight at a gallop. Rarely do horses choose to stay to fight a stimulus rather than leave the scene.
The last aspect of the equine mind is communicative behavior. Throughout each day, horses emit vocal and non-vocal signals to relay messages to other horses. Humans can learn to “speak horse” in order to better communicate with their horses. A great deal of communication occurs with body language, using the tail, legs, head and posture. Overall condition and mood of a horse can be determined by analyzing the body posture. A horse in pain, if not lying down, will typically display a wide stance with the head lowered and ears and tail hanging loosely. Leg gestures are commonly used in equine interactions. A threat of violence may be made by holding a leg momentarily in the air before an actual kick occurs. A horse may stomp one or more of its legs to signal irritation, frustration or anticipation toward both horses and humans, this can be seen prior to feeding time in a stabled horse or prior to an exciting race. Facial and tail gestures can yield the clearest information about a horse’s needs and desires. A sleepy horse will relax its neck and drop its head. The eyes will begin closing and the lower lip may relax. Forward, lateral or backward stimulus will cause the head to raise and the ears to turn in the respective direction. An aggressive horse will display bared teeth and laid back ears on a head that is lunged forward, while a horse experiencing pleasure will raise the head and twitch the upper lip. A horse’s tail stays relaxed and slightly elevated during normal situations, swishing at an occasional fly. However, certain breeds of horses, such as Saddlebreds and Arabians, will raise the tail considerably higher during work, as will most horses when excited. Pain, fear or submission will cause a horse to tighten the tail close to its body, sometimes causing the rump to clench under (Waring, 1982).
Horses also communicate with one another through the use of sounds, such as a squeal, nicker, whinny, groan or snort. A squeal is a “high-pitched outcry” (Waring, 1982, 198) that is typical during aggressive interactions. Three types of nickers have been distinguished (Waring, 1982). The first is the most common that humans hear most often when a horse is begging for something, such as food or release from a box stall. Stallion emit a special type of nicker when approaching a mare for breeding and mares reserve a quiet nicker to draw foals closer to their side. A whinny, or neigh, starts like a high-pitched squeal but end as a low-pitched nicker (Waring, 1982). A bored or tired horse will give a monotonous groan when standing relaxed or lying in a stall. Mares in labor pain will also softly groan with each contraction. A snort can indicate restless frustration when being restrained. Horses will also snore under two circumstances (Waring, 1982). A snore may be used to communicate with other horses prior to an alarm blow of the nostrils. Although not communicative, labored breathing while sleeping also causes the horse to emit a familiar “snoring” sound.