New sense discovered in dog noses: the ability to detect heat | Hacker News Reader

New sense discovered in dog noses: the ability to detect heat

sciencemag.org

98 pointspseudolus29 comments

But dogs’ rhinaria are moist, colder than the ambient temperature, and richly endowed with nerves—all of which suggests an ability to detect not just smell, but heat.

Interesting, I wonder if this has anything to do what looks like dogs licking their own noses when they get super excited, among other behaviors. Or at least my girl does, and I’ve always wondered what that was about.

Dogs lick their snot so they can taste things they've smelled recently.

Humidity helps smells travel. People doing dog sports that involve scent may have a spray bottle to moisten the dog's nose before their turn.

"All sensors are temperature sensors."

That's interesting! Never thought of it like that. Source? Original?

Not original, and I haven't been able to find out the author.

My background was originally in electrical engineering, where this is probably more widely known than in computer science.

Ha! hadn't heard that before but yep. CO2 sensor? photodiode? have a temp dependency. the nice ones are compensated and maybe give a coarse temp readout if i2c/spi enabled...

Technically if it is sensing infrared light directionally, it can be considered a crude low frequency eye?

Regardless of the ridiculousness of this question, I don't find any arguments against this.

There is this: https://en.wikipedia.org/wiki/Parietal_eye

But after a bit of consideration I do indeed prefer dogs to have three eyes now.

It might be stated even more interestingly than that, because it’s “directionally but not directly,” meaning it’s almost a “warp vision” picking up scatters and “seeing” around corners, right?

Sure, in the same sense that a mirage allows your eyes to see around corners?

I just realized now that dogs love to investigate thoroughly the two warmer areas of humans and other dogs. Around the mouth, and the other place.

Good god, it's called the crotch.

There's a text snippet autocomplete wouldn't predict.

No it taint, it's called the privates.

Well those tend to be the two smelliest parts on many people too. Armpits get an honourable mention.

But somehow dogs don't seem to care too much about armpits, in spite of being smelly and warm.

Dogs tend to go straight for the front and rear ends of other dogs for sniffing and licking too. They probably just want to know what you ate and when ;)

Hair bundle cells of the inner ear can also sense heat:

Thermal Excitation of the Mechanotransduction Apparatus of Hair Cells https://www.ncbi.nlm.nih.gov/pubmed/29395911

What a weird article. Humans can also detect heat. So is this is just about how some animals are more sensitive than others? Because I'm 100% certain that nobody in history has ever said "dog noses don't feel temperature".

It's not merely sensing heat, but sensing weakly radiating heat from a distance. The human researchers could only distinguish the test and control objects by touching them.

Did you actually read the article?

All the article says is that the nose of dogs is much more sensitive to heat than other animals, calling it a "new sense" is an exaggeration.

Humans also sense radiative heat from a distance. The only difference explicitly stated in the article is degree of sensitivity not a new sense.

But it can be a nuisance.

I think degree of sensitivity, discrimination, or directionality can warrant counting a 'new sense'. I would consider my sense of thermoreception to be different from that of a snake's heat-pits, or hearing to be a different sense from feeling vibrations.

As the article about epistemology posted yesterday mentioned, at some point, a difference in degree becomes a difference in kind.

This confused me as well. I didn't see anything in the article that distinguishes between the surface temperature of the nose being raised specifically via (a) infrared light vs. (b) some other source conductive heat transfer.

I'm not super familiar with mammal physiology, but I would think (a) counts as a new sense category, whereas (b) counts as a just a new understanding of how sensitive the nose is.

> I'm not super familiar with mammal physiology, but I would think (a) counts as a new sense category

> the surface temperature of the nose being raised specifically via (a) infrared light

If you've ever felt the sun on your skin, you've sensed heat from electromagnetic radiation.

If you've ever been in front of an infrared lamp or heater, you've sensed heat from infrared light in specific.

How would that be a new sense category?

Some are better than others: https://en.wikipedia.org/wiki/Infrared_sensing_in_snakes

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