RESEARCH - Study Shows Horses can Read Human Emotions

For the first time horses have been shown to be able to distinguish between angry and happy human facial expressions.

Researchers at the University of Sussex examined the reactions of 28 horses to photographs of people making positive and negative expressions, noting stronger reactions to anger. 

Amy Smith, a doctoral student in the Mammal Vocal Communication and Cognition Research Group at Sussex, co-led the research. She said: “The reaction to the angry facial expressions was particularly clear – there was a quicker increase in their heart rate, and the horses moved their heads to look at the angry faces with their left eye.”

Research shows that many species view negative events with their left eye due to the right brain hemisphere’s specialisation for processing threatening stimuli (information from the left eye is processed in the right hemisphere). The effect of facial expressions on heart rate has not been seen before in interactions between animals and humans.

Amy continued: “It’s interesting to note that the horses had a strong reaction to the negative expressions but less so to the positive. This may be because it is particularly important for animals to recognise threats in their environment. In this context, recognising angry faces may act as a warning system, allowing horses to anticipate negative human behaviour such as rough handling.”

A tendency for viewing negative human facial expressions with the left eye specifically has also been documented in dogs.

Professor Karen McComb, a co-lead author of the research, said: “Emotional awareness is likely to be very important in highly social species like horses – and our ongoing research is examining the relationship between a range of emotional skills and social behaviour.”

The details of the study are published in Biology Letters.