Those who study equines can identify plenty of ways the domestic horse has had to develop coping mechanisms related to a life lived in small, contained spaces with few companions. Many trainers point out that, in fact, most of the issues we run into when it comes to handling, training, or riding, are related to the stresses inherent in domestication. In her book What Horses Really Want, lifelong horsewoman Lynn Acton explores how horses want security and social bonds. As she explains, it is to their detriment, and to ours, when we deny them these basic needs.


The security of long-term social bonds is the exception for domestic horses. Many grow up without learning the social bonding skills to make positive connections with other horses, or to temper their own aggression or deflect that of others. The result is more aggressive behaviors, fewer social bonding behaviors. Even when they manage to make friends, those bonds are frequently severed because one horse is sold, moved, or switched to a different turnout arrangement.

Isolation often prevents horses from making social connections at all. Peering through bars at other horses is not social contact, and turnout in separate paddocks is a poor substitute for the physical closeness that provides security. The severity of the impact is shown in the fact that horses kept in stalls with little or no access to other horses are more likely to be aggressive toward humans.

Rank and Aggression

Rank is not typically determined by age, as in free-roaming bands. It is determined more often by “aggressiveness, temperament, or social experience.” Domestic living conditions often include the three factors most likely to cause aggression among horses:

  • Confined spaces increase the likelihood that personal space will be invaded, a common cause of aggression.
  • Having food supplied brings horses into close proximity, and invites guarding of resources. It is possibly the most significant source of aggression among domestic horses.
  • Artificial social groups with high turnover means that rank must be re-established with each change in group membership.

It is no surprise, then, that domestic horses spend more time in aggressive behavior and less time in social bonding behavior than their free-roaming cousins. These higher levels of aggression explain why people unfamiliar with free-roaming herd behavior mistakenly believe that rank is important to horses and that aggression is a normal part of herd behavior. This makes it easy to overlook the importance of social bonds.

Other aspects of domestic living also contribute to stress, and potentially to aggression:

  • Being confined is abnormal for horses. The less turnout time and space a horse has, the more likely he is to have behavior problems. When turnout is not possible, appropriate daily exercise is important for mental and physical health.
  • Lack of opportunity to use curiosity and explore their surroundings makes horses more fearful and less adaptable to new situations. Fearful horses are clearly a common problem. Consider the prevalence of calming supplements for horses; the anxious horses and riders one sees at many events, and the great interest in “de-spooking,” “desensitizing,” or “bomb-proofing.” How many horses are sold or relegated to pasture-ornament status because their owners are afraid to ride them? Horses’ reactions to anxiety-producing situations are intensified when they are already stressed by their living situations and/or inappropriate diets.
  • Diets high in carbohydrates and/or low in forage can contribute to stress-related behaviors and excitability. They are a risk factor for ulcers, which are found in 30% to 90% of domestic horses depending on the population studied. Such diets make horses more prone to aggression toward people, possibly as a result of gastric pain. Ulcers are rare or non-existent in free-roaming horses.

Leaders, Friends, and Social Networking

The shared leadership of free-roaming herds is based on a complex social network where horses decide whether to follow another horse based on their social bonds. Without these bonds, the system of leadership that is most natural for horses is not possible. Instead, a domestic social system may be a pecking order with rank determined by aggression. The highest-ranking horse may not be a leader any of the others would choose to follow, but a bully who has achieved rank through aggression while other horses do their best to appease or stay out of the way.


This excerpt from What Horses Really Want by Lynn Acton is reprinted with permission from Trafalgar Square Books (