Dogs that can predict when their owners are going to have an epileptic seizure may be recognising the “smell of fear”.
A small study suggests that a compound in sweat recognised by seizure alert dogs may be the same as one released when people watch scary movies, in this case Stephen King’s It.
Some animals communicate by releasing hormones that can be smelled, called pheromones, including ones that warn of danger, but it is unclear if human pheromones exist. …
Source: Dogs that detect seizures may be sniffing out the scent of human fear | New Scientist