Question: What areas of horse behavior would you personally like to see studied to a greater extent and why?
Renate Larssen: I am personally very excited about the prospect of learning more about equine emotions and how horses experience the things we do to them.
We know that animals have emotions just like we do. Feeling things is an evolutionary advantage, because it prompts us to act: to flee, to fight, to mate, to eat, and to bond, for example. Emotions keep us alive.
The tricky thing about studying emotions in animals is that we can’t ask them how they feel. While emotions manifest as observable behaviors, feelings are subjective experiences, and they will probably forever lie beyond our reach.
Traditionally, the study of emotions in domesticated animals focused on negative emotions like fear because they are easier to observe, easier to trigger in experimental settings, and have clear welfare implications. But recently there has been a surge in studies that examine positive emotions in animals, including horses.
A basic tenet when studying animal emotions is that negative emotions will trigger an escape or avoidance response, whereas positive emotions will trigger an approach. By gaging whether a horse will approach or avoid a person or a situation, for example, we can infer something about how it experiences that person or that situation.
One behavioral test that researchers use is the Motionless Human Test. It can be used to assess whether horses view humans as something good or something bad. I have used it in my own research, for example.
As the name of the test implies, an unfamiliar person stands completely motionless inside a small arena while the horse is allowed to move freely around the arena. By measuring how close the horse chooses to be, and how much time it spends near the unfamiliar person, we can get an idea of how that horse feels about people.
Another way to assess emotions in horses is to measure physiological and hormonal responses. I am particularly interested in the role of the hormone oxytocin in horse-human interactions. Oxytocin is often called the “love hormone” because it plays an important role in bonding between parent and offspring, and in facilitating social interactions between members of a group. This is true for both humans and other species.
Interestingly, recent studies have discovered that oxytocin seems to be involved in cross-species horse-human interactions, too. A paper published just last year by Niittynen et al. (2022) found that oxytocin levels increased over the course of a training session in horses that showed friendly behaviors towards the trainer, such as nuzzling and nipping. In contrast, oxytocin levels decreased in horses that showed strong flight responses such as bucking or bolting. Their result supports a few previous studies, for example by Lee and Young (2021), that found a similar correlation between oxytocin levels and friendly behaviors towards humans.
Research into equine emotions opens an exciting new avenue for exploring the horse-human relationship from the perspective of the horse. We already know that we like horses, but what do they think of us?
It’s a daunting question—and it’s entirely possible that we may not like the answer to it. But this is where I think ethological research should go next.
Do you have a horse behavior question for equine ethologist Renate Larssen? Send it to firstname.lastname@example.org for consideration in a future column.