Herding or Driving Behavior

The stallion is feeling a greater sense of urgency in this image exhibited by the exaggerated low driving posture.

wild horse photography of a stallion demonstrating herding behavior
In this image the stallion is exhibiting herding or driving behavior. The posture is one of lowered head, stretched neck, ears pinned and sometimes a snake-like back and forth head movement. There is more intensity here demonstrated by the exaggerated low posture and fast gait; the stallion was feeling some sense of urgency to redirect the mares.

Introductions

The stallion presents himself to a mare and foal.

wild horse photography of a stallion greeting a mare and foal
Stallion and mare responding to each other with matching postures while the young filly displays submissive gnashing in the presence of the stallion.