Can horses discriminate human body odors from joy and fear contexts?

Animals are commonly believed to detect human emotions through smell, in link with the primitive and ubiquitous characteristics of chemoreception. Indeed, the brain areas dedicated to odor processing are among the oldest structures in mammalian evolution, and chemosignals may play a role in interspecific communication. However, few studies have conclusively demonstrated that animals can perceive human emotions through smell. To determine whether horses can discriminate between human odors of fear and joy, a habituation-discrimination protocol was used. Horses were exposed to sweat odors from humans who declared they had experienced fear or joy while viewing a comedy or a horror film, respec…