Animals often use different sounds to communicate, but one study says horses in particular use more: their eyes and ears. (Via Thomas Quine / CC BY SA 2.0)
National Geographic reports that until now, scientists didn't know how large a part they play in horse communication.
According to a recent study in Current Biology, horses' highly mobile ears are visual cues to direct other horses' attention away from predators or toward food.
Researchers set up an experiment with about 70 horses to see if they used visual cues to decide from which of two buckets of food to eat.
BBC reports each horse was led to two buckets below a life-size photo of another horse. Some photos showed a horse with its eyes covered, some with its ears covered and the rest without anything covered.
The researchers say the horses that were shown the photos with both eyes and ears uncovered most often chose a bucket depending on where the photo horse's eyes and ears pointed to.
As for the horses who saw the other photos - with either the ears or eyes covered - they chose a bucket at random. And according to National Geographic, the researchers say this is the first of such evidence that horses signal to each other about food.
Now, this doesn't mean humans have never looked at horses' ears to read their body language before. But the researchers say previous studies have only focused on the animal cues humans use.
Horseback riders often pay attention to a horse's body language, such as the position of its ears, to determine if it's attentive or angry, for example. (Via Equestrian Life)
The study was published in the journal Current Biology. The researchers say they plan to study horses' facial features to express emotion.
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