Horses have long been known for their sensitivity to human emotions, but a recent study has revealed just how keen their sense of smell truly is. Researchers found that horses can actually detect fear in humans by smelling their sweat, leading to changes in their behavior.
The study, published in PLOS One, involved exposing horses to sweat samples from people who had experienced fear-inducing situations. The horses displayed signs of fear themselves, becoming easily startled, hesitant to approach researchers, and less likely to interact with unfamiliar objects.
Lead author Plotine Jardat, a horse behavior and welfare researcher, emphasized the importance of emotions in interactions with horses. “Our emotions are central when interacting with horses,” she explained. “If your horse is not cooperating, it may be worth considering your own emotional state as a factor.”
While previous research had shown that horses can respond to visual and auditory emotional cues from humans, this study delved into the realm of olfactory communication. By exposing horses to sweat samples from people experiencing joy and fear, researchers were able to gauge the animals’ reactions.
In one experiment, participants watched joyful movie clips before viewing a horror film to induce fear. Sweat samples from these individuals were then collected and presented to the horses. The horses that smelled the fear-inducing sweat exhibited less interaction with researchers and showed heightened reactivity to startling stimuli.
Additionally, when presented with a novel object, horses exposed to fear-inducing sweat were less likely to approach and touch it compared to control groups. These findings suggest that horses can indeed detect fear through scent alone.
The study raises intriguing questions about the evolutionary origins of this ability and its implications for human-animal interactions. While the exact mechanisms behind horses’ olfactory sensitivity to fear remain unclear, the research underscores the complex nature of interspecies communication.
As we continue to unravel the mysteries of animal behavior and cognition, studies like this shed light on the remarkable abilities of our equine companions. Whether it’s a subtle shift in their behavior or a dramatic reaction to fear-inducing stimuli, horses remind us of the deep connections that exist between humans and animals.

