We've all heard at least once that horses 'can smell your fear'. A study now suggests that this is indeed the case: horses can distinguish emotions by the smell of ... sweat.
Italian researchers have investigated whether horses' heart rates changed in response to different human odors. This showed that horses indeed reacted differently to a 'fear odor' than to a 'happy odor'. The aim of the research was to investigate how human emotions can influence the behavior of horses. This means it's probably not a coincidence that horses react differently to a nervous or anxious rider.
The study found that fear odor caused a higher heart rate in the horses, while a 'happy' sweat odor produced a quiet heart rate. Naturally, this research is only the basis for further research. For example, a more natural situation is needed (here the fear and cheerfulness stimuli in humans were evoked by watching a scary or cheerful video) to get more reliable results.
Source: bit magazine