You already know that dogs’ sense of smell is way keener than our own. But just how keen their sense of smell is might come as a surprise.
According to the clip, dogs’ noses have about 300 million olfactory receptor cells in their noses. Humans? A measly 5 million to 6 million. And in dogs, the system dedicated to processing smells takes up more relative brain area compared to humans. These disparities lead scientists to believe that dogs’ sense of smell is 10,000 to 100,000 times more acute than our own.
That’s pretty impressive. And unlike humans, dogs smell “in stereo” — that is, they smell separately with each nostril. That helps them figure out precisely where smells are coming from.
On top of that, dogs have a special organ called the vomeronasal organ, which lets them sniff out hormones released by animals and humans — alerting them to our emotional states, and even helping them tell when we’re pregnant or sick.