Rearing occurs when a horse or other equine "stands up" on its hind legs with the forelegs off the ground. Rearing may be linked to fright, aggression, excitement, disobedience, non experienced rider, or pain. It is not uncommon to see stallions rearing in the wild when they fight, while striking at their opponent with their front legs. Mares are generally more likely to kick when acting in aggression, but may rear if they need to strike at a threat in front of them.