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Human Sense of Smell Underestimated
Benjamin Long writes to note a study, by a team of neuroscientists and engineers, that demonstrated that humans can follow a scent trail — an ability that most had assumed only animals possessed. Furthermore, the study demonstrated for the first time that humans make use of differential information from the two nostrils. The researchers blindfolded college students who crawled through grass to sniff out a chocolate-scented trail. Here is the abstract of the paper in Nature Neuroscience. From the article: "The humans, however, still sniffed much more slowly than dogs, which may partially account for canines' greater efficiency at scent tracking. [A commentator] says that despite their relatively sluggish speed, the fact that subjects improved with training is noteworthy. 'I think that shows the effect of our distinctively different behavior in actually using this sense,' he says. 'The dog [has] been doing this its whole life, and humans [were] just asked to plunge in the first time they've ever done it.'"
As I understand it, the prevailing idea was that you had to walk around or move your head to identify the smoke gradient, whereas these new results suggest that you can get directional information just from nostril separation, the way you determine the direction of sounds.
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When we talk about our sense of taste in everyday conversation, what we are really talking about is our sense of smell.
The taste buds on our tongue have only four types of receptors: salt, sweet, sour, and bitter. Each has a specific region on the tongue -- for instance, bitter is on the back of the tongue.
All of the other qualities of food that we normally ascribe to taste are actually olfactory stimuli. When food is in our mouth, some of it wafts back up into our nose, where our most sensitive smelling tissue lies. This sensation is what we are referring to when we talk about the particular taste of chocolate, coffee, oranges, wine, etc. -- aside from their sweet, sour, salty or bitter qualities.
In humans, this sensitive smelling tissue lies inside the face behind the nose, in the nasal canal. In dogs, it's the wet tissue that makes up the surface of their nose. That's why dogs' sense of smell seems so much better than ours -- they are basically tasting the air and everything they get close to with their nose. You can smell about as well as a dog can, if you stick things in your mouth. But given what dogs are mostly interested in smelling, who would want to?
Computers are useless. They can only give you answers.
-- Pablo Picasso
In the NPR interview with the guys who ran the study, they said that it seemed that the only limit on the speed that practiced humans could track the scent was the speed they could crawl with their noses that close to the ground. That makes sense - I mean you can't crawl along with your nose literally in the grass at any kind of speed at all. A dog is able to run at full speed with it's nose just inches from the ground - and it's eyes are placed so it can still be looking forward as it does it.
So this may have nothing whatever to do with the sensitivity of our sense of smell and more to do with the shape of our head, neck and the length of our fore-limbs.
We mostly evolved to use our sense of smell for detecting whether food has gone bad or not - and for that, having nostrils right above our mouths is plenty good enough.
Dogs are evolved to track prey and find carrion - they need to be able to sniff and run at the same time.
Dog's noses are very impressive...it's incredible to see the kinds of tricks they can manage. But I wonder where that statement of "a million times more sensitive than humans" comes from - I bet it's something some journalist guessed at 100 years ago that we are all passing on as if it were the definitive answer. This study suggests to me that some simple practicing could narrow that gap considerably.
www.sjbaker.org
That's the point -- the question is whether you can identify the direction without following it! (Which, apparently is also possible.)
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That's why you always need at least one H1-B in your team, to take the fall.
Whenever you rip off a silent one, come over to Raji and ask him what kind of spices he puts in his food, then listen, not, and smile esoterically in plain view of your co-workers. As a bonus, the intern will think you are a nice guy for talking to him while everyone else accuses him of noxious flatulence for some resaon.
I understand your concern for dogs, but not all are treated like that. Most are either trained with clicker training (newer, not as widespread) or with the more traditional training which may use the shock collar--but I haven't seen it used in a very long time.I hope it went down like that with these kids too.
Most police dogs are trained to think of work as a 'game' and as such they only respond to the games commands. "Lets go to work" is the police-dog equivilant to telling your dog "Lets go play" and everything after that is a 'game' to them.
Human introspection is terribly inaccurate. Self-reporting is not effective, especially when it comes to psychometric testing. The things that humans do to bias studies are so subtle that they often don't know they're doing it. That's why Double Blind testing methodology exists.
So sorry, but you've missed the real point.
There are lives at stake here!
All of what you said is contradicted by basic primatology. We are not deer. We are great apes.
Great apes do not mark their territory with piss or pheromones. Great apes live in groups, so they don't need to smell each other to find each other -- they wake up with each other every morning, and go to sleep next to each other every night. They are all right in front of each other's faces.
Great apes attract and find mates based on vision, not smell. Have you ever seen a female chimp in heat? I have. Her hind end swells up to the size of a human buttocks. Here's a picture. With baboons, the labia become swollen and cherry-red. It looks like the mother of all veneral diseases.
This is true for out closest relatives -- gorillas, chimpanzees, orangutans, and bonobos. Sure, guys might be attracted to the scent of a woman, but what really gives you a boner is the sight of sexually mature breasts or a mature female butt with the wide hips. Porn is images, not smells.
When a human female menstruates, she is not leaking 'hormones'. It's not a stream of estrogen. The reason it's so exciting to wild animals is because she is bleeding and shedding endometrium tissue, and the animals are smelling blood.
Computers are useless. They can only give you answers.
-- Pablo Picasso
based on my college experiences, there are two scents that college students become very adept at tracking - beer and cigarettes. Well, make that three - beer, cigarettes, and pizza. And hearing, too - the Pssshh of a can of beer opening is very distinctive, much different than a soda.
Flappinbooger isn't my real name