Inter- and Intra-Species Communication of Emotion: Chemosignals as the Neglected Medium.
Authors: Semin Gün R, Scandurra Anna, Baragli Paolo, Lanatà Antonio, D'Aniello Biagio
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Humans unconsciously release chemosignals through body odour that convey emotional information to other species, a phenomenon largely overlooked in equine practice despite growing evidence from canine research. Semin and colleagues reviewed experimental evidence demonstrating that dogs exposed to human body odours collected during fear or happiness states display corresponding emotional responses, suggesting a direct inter-species transfer mechanism operating below conscious awareness. Preliminary equine data similarly indicates that horses exhibit differential autonomic nervous system activation when exposed to human fear versus happiness odours, implying they too are receiving and processing these emotional chemosignals. Given the fundamental dependence of modern equine management on close human-horse contact, this chemosignal pathway represents a previously unacknowledged channel through which handler anxiety, stress or contentment may directly influence equine physiology and behaviour independently of visual or auditory cues. For farriers, vets, physiotherapists and trainers, this framework suggests that managing one's own emotional state during handling may have measurable physiological consequences for the horse—a mechanism worth investigating in clinical contexts where handler-related stress has previously been attributed solely to behavioural or environmental factors.
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Practical Takeaways
- •Handlers and riders should be aware that horses can detect and respond to human emotional states via body odor chemosignals, potentially influencing equine behavior and stress responses
- •Maintaining calm emotional states during handling and riding may reduce stress-induced chemosignals that could negatively affect horse behavior and performance
- •Further research into inter-species chemosignal communication could improve training methods, veterinary handling procedures, and human-horse interaction protocols
Key Findings
- •Human body odors produced during emotional conditions (fear and happiness) contain chemosignals that communicate emotion across species
- •Dogs exposed to human fear and happiness body odors manifest corresponding emotional states to those of the human odor donor
- •Preliminary equine studies show that human body odors from fear and happiness conditions differentially activate the autonomic nervous system in horses
- •Chemosignal-based emotional communication occurs without conscious intent or awareness in human recipients