Let's Learn About Dogs' Noses

I thought I would write about the real estate market, or the Fed and the upcoming rate hikes, but that news is everywhere….

so to keep it interesting here is another digression from the financial world I work in:

Let’s learn about dogs’ noses!

We all know dogs have some amazing senses from which they get around in their world. Many of my clients have or have had blind or deaf, or partially so, dogs and they report that it is surprising how well they get around. Research is now suggesting that dogs have infrared radiation sensors in their noses!

Helen Czerski, in her wonderful Everyday Physics column in the Wall Street Journal provides some fascinating information. Our sense of temperature is dependent on our skin, and we pretty much have to touch something to find out about an object’s temperature, except maybe for a fire and its intense heat, or when we stare into our freezer wondering what to make for dinner. In the case of the fire, the infrared radiation heats up our skin. I wonder what is physically happening when we stand in front of the freezer to cause us to feel the cold in addition to the fact that our skin feels the lower temperature.

In physics there is a law that says anything warmer than absolute zero degrees ( -273C) loses energy by emitting photons of light, or electromagnetic energy, which are at frequencies different than visible light, so we cannot “see” the photons. Unless, of course, the object is very hot. Everything is always losing heat and emitting photons.

So, if you wanted to detect that radiation with an instrument the best way would be to have it colored dark so it would absorb light better (remember light is radiation) and cool, to have the biggest temperature difference from the object radiating the heat that you want to detect. I remember talking to my father-in-law, who designed infrared detectors for Boeing to be put into aircraft and the instruments were bathed in liquid nitrogen (- 320 degrees F, -196 degrees C) to help it be super sensitive to heat sources on the ground.

Anyway, back to dark and cool…. Think of a dog’s nose! Researchers at Lund University in Sweden have published findings that show that dogs can detect, from 5 feet away, a difference in temperature between 4 inch sized objects at room temperature and body temperature. The cold black nose absorbs the small amount of temperature difference and their nerves inside the skin can signal to their brains that a warm(ish) object is nearby.

Another amazing thing the research mentions is it appears that the dog’s nose warms up when it is sleeping and cools down within 15 minutes of waking. I guess the dog ramps up its instruments!

I remember learning that snakes, and maybe other reptiles, have infrared sensors in their heads. Maybe to either find warm prey, or a sunny rock on which to lie. Perhaps being cold blooded helps too.

So next time a dog’s cold nose touches your skin you can remember there is more there besides a very good “smeller”.