If a horse has a concave or dished face profile, it is often further emphasized by a slight bulging of the forehead (jibbah). Dished heads are associated with Arabians and Arabian-influenced breeds, which excel at endurance riding and were originally bred in the arid Arabian desert. There are several theories regarding the adaptive role of the dished face. It may be an adaptation to reduce airflow resistance and increase aerobic endurance. It may also have a role in cooling inspired air, or cooling blood headed to the brain.
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