THE PERFECT SENSE

The nose of the dog: have you ever looked after the nostrils of dogs? They have a comma shape with the opening narrowing to the side: a very efficient system to separate the air that enters, through the central passage, from the one that exits through the leg of the comma. Dogs perform about 8 sniffs per second, up to 12 if they are actively sniffing something.

At this speed the odorous molecules would go in and out too quickly, instead the nose of the dog (and other mammals) holds them longer. Part of the inspired air goes directly to the bottom of the nasal cavity which "collects" the odorous molecules; another part of the air is instead sent to the rest of the respiratory tract (third photo). During several consecutive sniffs, the molecules are concentrated in an area called the olfactory recess and can thus be perceived better. I also talk about it in the Instagram stories.

Dogs have a great sensibility to odors thanks to the shape of their nose (not only): the nostrils have a “comma” shape that enables them to separate the air coming in and out the nose. The main air stream reaches directly the deep of the nose where odorant can concentrate, while a second airstream goes for breathing.