A new study published in the journal Royal Society Open Science provides the first evidence of how goats (Capra aegagrus hircus) read human emotional expressions.

Faces are some of the most important and salient classes of stimuli involved in social communication for both human and non-human animals.

In the case of domesticated animals, both conspecific and heterospecific facial expressions are informative. However, it is not clear whether animals, in general, or those domesticated primarily for production are able to distinguish between different human emotions based on facial expressions.

To test this, University of Roehampton researcher Alan McElligott and co-authors presented goats with positive (happy) and negative (angry) images of unfamiliar human faces.

“In the study, we investigated whether goats can distinguish human facial expressions when simultaneously shown two images of an unfamiliar human with different emotional valences (positive/happy or negative/angry),” the researchers explained.

“Both images were vertically attached to a wall on one side of a test arena, 1.3 m apart, and goats were released from the opposite side of the arena (distance of 4 m) and were free to explore and interact with the stimuli during the trials. Each of four test trials lasted 30 s.”

“The study was carried out at a goat sanctuary (Buttercups Sanctuary for Goats) in the United Kingdom.”

The team found that images of happy faces elicited greater interaction in the goats who looked at the images, approached them and explored them with their snouts.

This was particularly the case when the happy faces were positioned on the right of the test arena suggesting that goats use the left hemisphere of their brains to process positive emotion.

“This study has important implications for how we interact with livestock and other species, because the abilities of animals to perceive human emotions might be widespread and not just limited to pets,” Dr. McElligott said.

“We already knew that goats are very attuned to human body language, but we did not know how they react to different human emotional expressions, such as anger and happiness,” said study first author Dr. Christian Nawroth, from Queen Mary University of London and the Leibniz Institute for Farm Animal Biology.

“Here, we show for the first time that goats do not only distinguish between these expressions, but they also prefer to interact with happy ones.”

This study has implications for understanding how animals process human emotions.

“The study of emotion perception has already shown very complex abilities in dogs and horses,” said co-author Dr. Natalia Albuquerque, from the University of Sao Paulo.

“However, to date, there was no evidence that animals such as goats were capable of reading human facial expressions.”

“Our results open new paths to understanding the emotional lives of all domestic animals.”

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Christian Nawroth et al. 2018. Goats prefer positive human emotional facial expressions. R. Soc. open sci 5: 180491; doi: 10.1098/rsos.180491