Tuesday, August 31, 2010

The dog days of August: How humans have shaped the canine sense of smell

One of the most unshakeable bits of conventional wisdom about smell is that the nose of the dog is vastly superior to our own. In my book, I took a few potshots at this shibboleth; I pointed out that (a) molecule for molecule, the sensitivity of the human nose is competitive with that of the dog, and (b) plenty of human nasal talents sound amazing if given equal hoopla. (Amazing human ability: people can identify the geographical origin of the wood in a popsicle stick by the flavor it leaves in the ice cream!)If we are on a par with dogs when it comes to odor detection under lab conditions, why don’t we outperform them on a daily basis? What dogs have going for them is that they devote more of their brain to analyzing and interpreting scent signals than we do. To a far greater degree, their life revolves around odors.

In What the Nose Knows, I proposed that human odorant receptors evolved to track our biological traits of cooking and seasoning food. I cited evidence that “in the last 5,000 to 10,000 years, genes for smell receptors, along with genes related to diet and metabolism, have been evolving faster than those in any other physiological system.” I speculated that this may have had consequences for our long friendship with dogs.
I also suspect that dogs are part of the whole story. Dogs were first domesticated by man somewhere in Siberia about 15,000 years ago, just as humans populations were shifting from a hunter-gatherer existence to sedentary village life. Increasingly preoccupied with the complex man-made aromas of the cooking pot, our ancestors began to rely on hunting dogs to locate the telltale scent of game. Having co-opted the canine nose, our own scent-tracking ability began to fade. Dogs became, in effect, our long-distance noses, while we specialized in the close-in smelling of food in the mouth.
Two recent studies on canine evolution got me thinking again about human-canine co-evolution. The first was a comparative analysis of cranial and brain anatomy of thirteen different dog breeds. It was conducted by a trio of Australian scientists led by Taryn Roberts at the University of Sydney. Her team notes that the grey wolf, the immediate ancestor of the domestic dog, is dolichocephalic; that is to say it is has a long, relatively narrow skull. Some breeds of domestic dog, such as greyhounds and Russian wolfhounds, still display this trait. Many other breeds are bradycephalic (short-skulled); they retain the flat-faced, snub-nosed look of puppies. (Think Maltese or Staffordshire bull terrier.) As the authors say, “canine bradycephaly is purely a human invention,” the result of selective breeding over the past few thousand years.

Using MRI images of skull and brain, the Roberts team calculated a Cephalic Index (skull width / skull length x 100) for each breed. They also charted the anatomy of the olfactory bulbs—the first processing point in the brain for odor information from the nose. As in humans, the dog’s olfactory bulbs are located just below the frontal lobes of the brain. It turns out that as one moves from long-skulled to short-skulled breeds, the brain tilts downward and the olfactory bulbs change their relative position—they move further below and to the rear of the frontal lobes. This remarkable rotation depends entirely on the Cephalic Index; a breed’s overall body size or weight have nothing to do with it.

How does this human-induced change in olfactory neuroanatomy affect each breed’s sense of smell? That’s the big question, one the authors say is “of intense interest for future research.” I hope we’ll be hearing more soon.

The other dog paper that caught my eye is called “Tracking footprints of artificial selection in the dog genome.” It’s a highly mathematical analysis of a large-scale DNA dataset: more than 21,000 gene loci taken from 275 dogs from 10 breeds. The researchers—from four different institutions across the United States—combed through this enormous pile of data using statistical filters that picked up genetic variation consistent with artificial selection, i.e., evidence of selective breeding. They found 155 genetic regions that met the criteria, including all five genes linked to breed-specific traits in previous, smaller scale studies. (One gene, for example, is associated with skin-wrinkling in the Shar-Pei.)

Although they don’t specifically mention olfactory gene regions that might vary between breeds, the authors raise another, rather provocative, possibility. They note that for many gene locations associated with positive selection in the dog, there are analogous locations in humans.
Although this result should be interpreted with caution, as the specific targets of selection are generally not known with certainty in either dogs or humans, it does raise the intriguing possibility that recent selection has influenced common loci in both the human and dog lineages.
Translation: to some extent dogs and humans have coevolved at the genetic level.

Would it be too big a stretch to think this might have to do with our shared food? Every cooked and spiced scrap tossed to the dogs might have helped shape their olfactory ability. And every gazelle felled by an arrow after being scented by hound would just keep the feedback loop going.

Sunday, August 22, 2010

How’s That “One Mighty Drop” Thing Working Out?

In an effort to halt a massive slide in perfume sales, the Fragrance Foundation launched a new campaign back at the end of January called One Mighty Drop. Like all cooperative advertising efforts—remember “The other white meat” by the National Pork Board?—the Fragrance Foundation created a nifty slogan: “One drop changes everything”. It also created a weak-ass web site decked out in a psychedelic motif left over from the Yellow Submarine era.

We weren’t the only ones skeptical about this approach. Being nerdish, however, we decided to start tracking the Alexa web traffic rankings of OneMightyDrop.com as a measure of how well it was getting the word out. Today we present the results.

If it’s going to create awareness, the One Mighty Drop web site should draw as much or more traffic as the fragrance blogs we track on the Smell Web Indexes. For the initial week ending February 28, OneMightyDrop was ranked 2,722,004. So for comparison we selected the team blog ISmellThereforeIAm (ranked 2,380,754), and the solo blogs GrainDeMusc (2,674,125) and AyalaSmellyBlog (3,118,021).

How did they all do? Let’s go to the numbers:

Alexa rankings for all four sites stayed were steady until about a week after the FiFi Awards on June 10. At that point OneMightyDrop.com began to fall away from the pack. In mid-August it sank abruptly and last week it went into a full nose dive.

Here at FirstNerve we call that one mighty drop-off.

The Fragrance Foundation would have gotten its message out more effectively by enlisting some well-regarded fragrance bloggers. Just sayin’.

Meanwhile, all these years later, TheOtherWhiteMeat.com is ranked 361,126 worldwide and 74,066 in the U.S. It has 248 sites linking into it versus 6 for OneMightyDrop.com. Looks like the perfume industry has been outplayed by the pork producers.

Thursday, August 19, 2010

From Mouse to Nose

This BizBash post is a bit over-hyped but the Brazilian HW/SW combo for delivering a Web-linked scent sample to Internet cafe customers is kinda clever in a home-brewed sorta way.

Monday, August 16, 2010

NPR: The Best Radio Journalism Your Tax Dollars Can Buy

What a lame twenty-nine seconds.

P.S. Something tells me that Linda Wertheimer likes the smell of her own farts.

P.P.S. If you fart into a $20 NPR Organic Cotton Large Grocery Tote, you can smell it again and again while you’re in the studio. And you don’t have to worry about audibilizing with an open mic.

Friday, August 13, 2010

Green and Stinky: UK Biofuel Plant Upsets Locals

Al Gore, call your aromatherapist.

Euphemism alert: According to the BBC, the biofuel company plans to reduce the offending odor by installing “oxidising equipment.” Apparently that’s how the environmentally committed media refer to exhaust stack burners.

Exit question 1: Should a biofuel company buy carbon offsets when it de-smellifies its production line by burning the exhaust?

Exit question 2: Should the people who deal with odor problems at composting facilities and biofuel plants be counted as “green jobs”?

The FirstNerve BurrOmeter: Mailing It In

Name Drops: 1

Jean-Claude Ellena
Bonus Points:
Perfumers: 1
French: 1
Jean-Claude Ellena Deluxe Triple Bonus Points®: 3

Nonsensical fragrance descriptions: 3
marvelous filigree of citrus
heated granite
sweet midnight in summer
Calibration factor for micro-mini review format: 10-1

Total BurrOmeter reading for Eau Claire des Merveilles: 0.9 milliburrs

Outlook: Lowest reading ever recorded. The trendline is headed for the microburr range.

Thursday, August 12, 2010

ISDP: Taking the Initiative

Better than a full moon on Halloween, it’s an ISDP classic: a Friday the 13th edition just like our very first. So if you’re neither spooked by the date nor creeped out by the lugubrious subject matter, cursor on down for our latest roundup of the worst possible smells in the hottest part of the year.

We begin in Hagerstown, Maryland.
Neighbor Heather Burke and her husband, Kevin Allen, said they had been complaining to their landlord about a foul odor coming from the neighboring home, in the same duplex, since they moved in two weeks ago.
Complaining doesn’t butter the biscuit. Sometimes you need to take action.
On Sunday morning, Burke again complained to the landlord about an odor and the two went into the home to search for its source, she said. She said she discovered what looked like a body in an upstairs bedroom and, scared, ran out of the duplex. 

Approached for a comment, the landlord waved off a reporter.
We're inclined to cut the landlord some slack: at least he finally opened the door. 

Even the tony precincts of Palm Beach, Florida are not immune from macabre malodors. Here’s a Bastille Day report from the Palm Beach Post:
Neighbors had noticed a foul smell and had even searched the area for what they figured was a dead animal but never found the decomposing body of a man lying in bushes and underbrush behind the 1100 block of 35th Street.

“My husband said it was probably a dead rat,” said Chavela Graham, whose property line ends just feet from where the man was found by a city worker. “The stench was getting worse.”
Good guess, Mr. Graham! (It’s unclear if he actually got off his duff and joined in the search . . .) 

We’ve had a few ISDP incidents in Kansas City, but the discovery of a decomposing body on July 28 makes the place sound like a ghost town:
Someone called police about 2 p.m. today to report a foul odor coming from the closed Paradise Motel, which is across the street from a closed liquor store and deli. The body was in a guest room.

Sorry, Paradise is closed but you can leave the body in number six.

Which brings us to a related story from San Antonio:

City targeting motel with ‘scent of death'
We are generally sympathetic toward the small businessman trying to make a go of it, but the Alamo Lodge has a pretty ugly track record, including this:
A health inspector on Jan. 12 found bloodstains on a box spring in a room at the motel; animal feces; dead bed bugs; cockroaches; urine smells; and, in room 124, there was a “scent of death.”

The report was unclear if it referred to the death of an animal or a person.
That’s not an easy call to make; just ask Mrs. Graham’s husband.

Finally, we have new candidates for the Norman Bates Award, International Division.
He was thought to be the oldest man in Tokyo - but when officials went to congratulate Sogen Kato on his 111th birthday, they uncovered mummified skeletal remains lying in his bed.

Mr Kato may have been dead for 30 years according to Japanese authorities.
Turns out Kato-san’s entire family may have been pulling a Norman Bates.
. . . the family had received 9.5 million yen ($109,000: £70,000) in widower’s pension payments via Mr Kato’s bank account since his wife died six years ago, and some of the money had recently been withdrawn.

Mr. Kato probably stopped smelling bad 29 years ago, but since his demise was discovered only this month, the ISDP Awards Committee has ruled that his family is eligible for the 2010 competition. Good luck and thanks for playing!

UPDATE August 21, 2010
The case of the mummified Mr. Kato is just the tip of an iceberg. According to this story by David McNeill in The Irish Times, many other very elderly people on municipal rosters in Japan cannot be found.

Around the country local authorities have been literally calling door-to-door since to determine how many more pensioners are “missing” – officially recorded as alive but actually long since departed to the great bureaucrat-free nirvana in the sky.

So far, they have uncovered over 280 (of 41,000 recorded) centenarians who have “vanished”. Nagano health officials crossed out the name of a 110-year-old man officially registered as the prefecture’s oldest person.

In Kobe city, the missing include a 125-year woman – making her Japan’s oldest person.


Wednesday, August 11, 2010

The Time I Met Frida Kahlo

[images copyright Alice Gilbert]

Tuesday, August 10, 2010

Rhymes with Van Halen

My third post on FirstNerve, way back in September 2008, was a fishy one. It involved a school of menhaden that has been driven into the shallow waters of the Shellbank Basin off Jamaica Bay in Howard Beach, Queens, by predatory bluefish. Starved of oxygen in the warm waters, the menhaden died and raised a major stink.

A few months later, three thousand or so menhaden swam into an algae bloom in Baltimore harbor. Low oxygen, yadda yadda, big stink.

Well, it’s late summer and here we go again. The folks in Fairhaven, Massachusetts, an inlet above Buzzard’s Bay, are pinching their noses as thousands of dead menhaden wash up on the beach. Warm water, oxygen, yadda.

A few days earlier it was a man-made stinkfest off Buckroe Beach on the lower Chesapeake Bay near Norfolk, Virginia. A commercial fishing operation (they make fish oil and fish protein out of this inedible species) had scooped up an ass-load of menhaden in a purse seine. The catch was being suctioned aboard the trawler when a hole developed in the net and about 75,000 dead menhaden (low oxygen in net, yadda) spilled out. 

Menhaden seem optimized for reproduction but not especially good at surviving in, or staying out of, low oxygen waters. Still, it makes one wonder about their evolutionary trajectory as a species. They’ve probably been doing this for a million years or more.

UPDATE August 11, 2010
As of this morning, tens of thousands of dead menhaden are rotting on the beaches of Delaware Bay near Cape May, New Jersey. Maybe it was the mention of Van Halen.

Could this all be a marketing gimmick for Piranha 3D? (I’m so there . . .)

Thursday, August 5, 2010

One for the Road?

Tara Wallis-Finestone has the story at NBC Los Angeles:

A Toluca Lake woman was recently kicked off a Delta Airlines flight after reporting that she thought she had smelled alcohol on the captain’s breath.
The story is headlined “Woman kicked off flight after accusing pilot of drinking” but a more accurate version would be “Woman kicked off flight after falsely accusing pilot of drinking.”

After the woman’s accusation was brought to their attention, Delta tested the pilot and determined he had not been imbibing. The pilot then exercised his prerogative and had the lady removed from his plane. (She received a hotel room and a later flight.) Despite the huffing and puffing of some online commenters, this seems to me to be a reasonable action. Among other things, there was a risk she would continue her accusations and create fear among the other passengers. 

I have no doubt the lady from Toluca Lake was sincere; but being wrong about such an accusation has consequences too. And detecting alcohol on someone’s breath is not all that easy. It’s a topic I took up in What the Nose Knows, immediately after a skeptical treatment of the ability of police officers to smell unburned marijuana.

When it comes to detecting drunk drivers, sniff-based forensics are on even shakier scientific ground. A study by the National Highway Transportation Safety Administration found large variability in the ability of police officers to smell alcohol on a person’s breath. As a group, cops picked up the scent consistently only when the drinker had a very high blood alcohol level (the detection rate was 61% for BACs between 0.10 and 0.15%).