A study of Wathan and Karen McComb, researchers of the University of Sussex (United Kingdom) Over the media of animals with large mobile ears, It has led them to elaborate the dictionary of horses. This equine dictionary consists of a database baptized as EquiFACS whose objective, in addition to deepening their research to better understand equine language, is to compile a series of signals with universal meaning.
The dictionary is in its first phase of development and only describes the movements, so it still does not offer the exact meaning until the previous coding work is completed.
To bring about EquiFACS, Wathan and McComb they collected pictures documenting horse expressions and they used them to life size to show them to other copies offering them concrete messages, like for example, to indicate to the exact place where the food is.
Thus, they were able to confirm that the position of eyes and ears is especially important in your communication, even more than whinnies or head position.