Horse behavior is best understood from the view that horses are prey animals with a well-developed fight-or-flight response.
Their first reaction to a threat is often to flee, although sometimes they stand their ground and defend themselves or their offspring in cases where flight is untenable, such as when a foal would be threatened.
Through selective breeding, some breeds of horses have been bred to be quite docile, particularly certain large draft horses.
On the other hand, most light horse riding breeds were developed for speed, agility, alertness, and endurance; building on natural qualities that extended from their wild ancestors.
Horses' instincts can be used to human advantage to create a bond between human and horse.
These techniques vary, but are part of the art of horse training.
This survival mechanism still exists in the modern domestic horse.
Humans have removed many predators from the life of the domestic horse; however, its first instinct when frightened is to escape.If running is not possible, the horse resorts to biting, kicking, striking, or rearing to protect itself.Many of the horse’s natural behavior patterns, such as herd-formation and social facilitation of activities, are directly related to their being a prey species.The fight-or-flight response involves nervous impulses which result in hormone secretions into the bloodstream.When a horse reacts to a threat, it may initially "freeze" in preparation to take flight.The fight-or-flight reaction begins in the amygdala, which triggers a neural response in the hypothalamus.