Anyone who has lived with dogs will have noticed that they often seem to know when it is their walk time, meal time, or even when a family member is about to return home. And it is completely true: although the concept itself is something human, dogs know exactly what time it is. Or rather, when they have to do certain things.
At a less conscious level, the dog's own body knows what time it is due to the cycles of day and night, which affect not only the intensity of light but also variations in temperature. But the best friend of the human being also has other mechanisms to determine at all times the passage of time, the routines of the people with whom he lives and when the time of his favorite activities ... or detested approaches.
The most powerful of these mechanisms is their extraordinary smell, which is between 10,000 and 100,000 times more powerful than humans, so that changes in the environment that are imperceptible to us are evident to them. Dogs have a built-in biological clock: the truffle, that is, their nose. Each person - each being, in fact - has a unique smell, which comes mainly from the particles that are shed from the skin. Even if someone leaves the house, their characteristic odor remains on these particles.
This smell, however, fades over time, and that's where the olfactory arsenal of dogs comes into play: by licking the truffle, apart from hydrating it, they are capturing these odorous particles and transmitting them to their smell, which is so powerful. which is capable of determining the concentration of these. If the inhabitants of the house follow regular hours, the variation in this concentration tells them how long it has been since someone left and, therefore, when they are likely to return.
Dogs are able, in fact, to "smell" time in a similar way to how a person would determine it by looking at an hourglass or water clock. Alexandra Horowitz, Ph.D. in Cognitive Science and author of several books on canine behavior, explains how odors in a room change as the day progresses:
“Hot air rises and usually flows in streams along the walls up to the ceiling, heads toward the center of the room, and falls. If we could visualize the movement of the air throughout the day, what we are really visualizing is the movement of the smell throughout the day”. Those scent cycles are also what allows them to anticipate daily activities that occur at set times, such as eating or going for a walk.
Although their sense of smell is a precision clock, it is not their only trick to anticipate the behavior of the people with whom they live. Dogs are masters of observation when it comes to facial and body language and thanks to that they are able to relate certain actions or expressions with a specific consequence.
Through behavioral experiments, it has been shown that they can even differentiate the results of similar behaviors through minimal changes in facial expression, tone of voice and even body posture: that feeling that the dog knows when they are trying to deceive him, promising taking a walk when the real intention is to bathe it, is completely successful. (Text and photo: National Geographic)