A new study shows that horses respond to chemical signals carried in human odor secreted in fearful situations: even without eye contact, body language or facial expressions, they become more alert and more reactive to sudden events when they smell humans’ fear.
Humans have long believed that horses can “smell the fear“. Nervous riders are often advised to “relax, or the horse will feel“However, until recently, there was little scientific evidence to demonstrate whether this was something more than folklore.
A new one has now concluded that this belief it is not a myth. Their results, published last week in PLOS Oneshow that horses can detect chemical signals linked to human emotions, and that these signals can influence their behavior and physiology.
Previous investigations pointed to a form of emotional contagion between humans and horses. This is a phenomenon in which the emotional state of a person or animal influences the emotional state of another.
But this is the first study to find evidence that horses can detect human fear through your sense of smell.
The horses rely heavily on your sense of smell to understand the world around them. Their olfactory system is much more sensitive than ours, allowing them to detect subtle chemical differences in the environment.
There is scientific evidence that horses can select the most nutritious food through smell. One published in Science Direct in 2016 concluded that horses choose food based on nutritional contentlike proteins, and not just in taste, and the way your body reacts after ingestion influences future choices what they do about food.
Then, How can horses smell our fear?? Well, human emotions are accompanied by physiological changes, says the professor Roberta Blakefrom Anglia Ruskin University, in an article in .
When people feel fear or stress, your body, face and voice change. The body also releases hormones such as adrenaline and or cortisolthe heart rate increases and the composition of sweat changes.
These changes modify the chemical profile of body odor of a person, which can carry information about their emotional state.
The smell of fear
The new study found evidence that horses not only detect but also respond to human emotional odors. The horses in the study were exposed to human body odors collected through cotton pads passed under people’s armpits.
In the investigation, participants watched either an excerpt from the 2012 horror film “Sinister”, to induce fearand scenes like the dance to “Singin’ in the Rain”, to induce joy. The researchers also collected control odorswithout any emotional association.
The horses showed distinct behavioral and physiological changes when exposed to odors related to fear, present on cotton pads, fixed by a nylon mask on the muzzle: became more alertmore reactive to sudden events and less inclined to approach two humans.
Furthermore, they presented increases in maximum heart ratewhich indicates stress, during exposure to the smell of fear from sweat. Crucially, these responses occurred without any visual or vocal cues of humans showing fear.
This discovery shows that the smell alone can influence the emotional state of a horse. The horses weren’t responding to tense body language, facial expressions or nervous movements – they were just responding to chemical signals carried in human odor.
These findings are consistent with the so-called emotional contagionwhich has been documented between humans and dogsfor example, and suggest that horses can also be affected by human emotions.
The study does not suggest that horses understand fear in the same way as humans, or that know why a person is afraid. Instead, evidence shows that horses are highly sensitive to the chemical, visual and vocal cues associated with emotional states.
The sense of smell is probably just a part of a physiological system wider. Horses are skilled at reading human posture, muscle tension, breathing patterns, heart rate and movement – all of these change when a person is anxious. These signals shape how a horse perceives and responds to a human.
Understanding how horses perceive human emotions has important implications for your well-beingtraining and safety. Riders, handlers and therapists who work with horses can unintentionally influence an animal’s emotional state through their own stress or calm.
The investigation It also challenges outdated assumptions about animal perception. Horses are not passive responders to human commands, as equine professionals and researchers thought until recently. They are sensitive social partnersfinely tuned to the emotional signals we emit.
