Since childhood, we've been taught that you shouldn't be afraid of dogs. More precisely, you shouldn't show your fear to a dog—after all, they supposedly sense it. Let's figure out whether this is true or just another myth (of which there are so many in our world).
Everyone knows that dogs' sense of smell is unique, playing a vital role in their lives. Furthermore, dogs' sense of smell is closely linked to their brain structure and performs many vital functions. It's worth noting that the area of the brain that controls olfactory function in dogs is 40 times larger than the same area in humans!
A dog's nose is always moist—it's coated with mucus, which breaks down odors into their individual components. Scientists claim that dogs can detect odors from as far as 1 km away, and there's a special bump on the roof of their mouths that detects pheromones.
When we feel fear, our body begins to release adrenaline and norepinephrine, which causes some almost immediate changes, triggering a fear and stress response. The release of these volatile substances dramatically alters the odor of sweat, and dogs can detect this. Numerous experiments have shown that dogs easily detect increased adrenaline levels in their blood. However, animals don't specifically associate the scent of adrenaline with fear. For a dog, this scent signals anxiety, so the behavior of the person who is afraid of the dog is crucial. Their voice, facial expressions, movements, and other behavioral patterns can trigger aggression in a dog.
Interestingly, in one experiment, participants merely feigned fear, using characteristic body movements and gestures. Half of the subjects received adrenaline injections, while the other half did not. Nevertheless, dogs from both groups reacted equally aggressively to people. This led to the conclusion that dogs truly sense fear. Physiologically, the scent of adrenaline serves as a signal to them of human anxiety, but the human behavior itself is a more significant indicator of fear.
