When I walk in the house after being at the rescue, my dogs are all over me. They sniff my pants from ankle to hip, noses vibrating with excitement. And why not? So many other pups to smell!
But sometimes when I come home after being nowhere near another dog, they are equally interested in the odor of my pants. I know a dog’s sense of smell is far superior to mine, but how superior? And what about a dog’s other senses?
SENSE #1 SMELL
An oft-cited study conducted by researchers at the Sensory Research Institute at Florida State University posits that a dog’s sense of smell is 10,000 to 100,000 times more acute than human’s. That’s difficult to imagine, isn’t it? Borrowing head scientist James Walker’s analogy to vision, if a person can clearly see an object ten feet away, a dog could see that object clearly from almost nineteen miles away.
SENSE #2 SIGHT
MYTH: Dogs do not see the world in black and white.
Because scientists have studied dogs’ retinas, we are able to know more about what they see and how they visually perceive their world. The layman’s version: dogs see like a color-blind human. They can see blue-violet and yellow, and differentiate between shades of gray. They typically have 20/75 vision, so they need to be 20 feet away from an object to see it as well as we see it from 75 feet away.
So when your dog comes running to you from across the park, he’s probably smelling you before he sees you. Or he’s hearing you…
SOUND
Super simple science lesson. Hearing has multiple facets: frequency and volume. In terms of frequency (think pitch), people can hear a bit lower, but dogs upper ranges blows us away. The human range is 20 – 20,000 Hz, and a dog’s is 67 – 45,000 Hz.
In terms of volume, dogs can hear sounds as quiet as 5 to 15 decibels (a human whisper is 20 to 30 decibels). It makes sense then, that even noises that aren’t deemed too loud for people can bother a dog.
TOUCH
No, those hairs above your dog’s eyes aren’t extra long lashes; they are whiskers that are so sensitive to touch that he can sense changes in airflow before he even touches an object. Like humans, dogs respond to touch on all parts of their body, and it’s wise to habituate a puppy to being touched. It’s also wise to ask a dog’s human how he likes to be petted before touching a new-to-you pup.
TASTE
If you’ve ever tasted dog food or treats (I did, on a dare from my younger sister when I was a kid), you know that dogs and humans have different ideas of what tastes good. Dogs have 1700 taste buds compared to humans’ 9000, but their superior sense of smell guides their food preferences. Two other fun facts: dogs have taste buds for water, and they don’t have an affinity for salt like we do.
*****
So whether the way to a dog’s heart is through his stomach or his nose, his senses dictate how he perceives the world around him. And if that means my dogs can’t keep their noses off my skinny jeans, I’m happy to let them sniff away!