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Of Biosensors and
Buddy's Nose
by Sue Ann Bowling
Alaska Science Forum August 15, 1989
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This article is provided as a public service by the Geophysical
Institute, University of Alaska Fairbanks, in cooperation with the UAF research
community. Dr. Sue Ann Bowling is an Associate Professor of Physics at the
Institute.
They haven't got no noses,
The fallen sons of Eve;
Even the smell of roses
Is not what they supposes;
But more than mind discloses
And more than men believe.
-- G. K. Chesterton,
"The Song of Quoodle"
The German Shepherd zigzags across
the raw, snow-patched earth ahead of his handler, nose to the ground. Suddenly
he stops, concentrating on a bit of earth no different from any other to
human senses, then begins to dig furiously. His handler rewards the dog with
a tidbit and an affectionate hug, flags the spot the dog has marked, then
sends the dog out ahead again, searching for more pipeline leaks.
Pipeline leaks? Found by a dog?
Back in 1974, a new buried natural gas pipeline was due for opening in Ontario.
The line, however, leaked -- and engineers and scientists using every bit
of technology at their disposal had been unable to find the leaks. Sections
of the pipeline would literally burst from overpressure before the leak rates
became high enough to be detected. The line was due to be opened in just
nine days when someone thought to consider dogs and contacted dog trainer
Glen Johnson.
Johnson took three dogs already trained in scent work, and in two and a half
days taught them to dig for a buried article where they smelled the butyl
mercaptan used to "odorize" the natural gas. Then they tackled the first
twenty miles of the pipeline, where the pipeline workers thought there might
be three small leaks. The dogs found twenty the first day. "Impossible,"
was the verdict -- until the indicated sections were dug up and the leaks
finally found. Eventually, the dogs found 150 leaks.
Where odorous compounds are concerned, technology still cannot match a dog's
nose. The dogs on the pipeline were identifying odors at forty feet that
chemists could not detect at all, and were responding to concentrations in
the parts per trillion range.
People probably domesticated dogs to use their noses in finding game, and
that ability must have been extended to the finding of lost children and
fugitives very early. Sherlock Holmes used a tracking dog in one of his cases,
and the fugitive slave or criminal pursued by slavering bloodhounds is a
stock piece of American fiction. (In fact, the bloodhounds drool because
of the loose facial skin which helps direct scent to their noses, and would
be more likely to drown an escaped prisoner as they licked his face than
to attack.)
In this technological century, we have found new ways to utilize the dog's
nose. Dogs have been used to detect gypsy moth egg masses, fire accelerants
used by arsonists, drugs, explosives, firearms, utility line leaks under
the streets of downtown New York, and termites, as well as the more traditional
victims of avalanches, earthquakes, and just plain getting lost.
Dogs' noses are also used in sport. Hunting dogs are well known, but dogs
of all breeds can compete in advanced obedience work, where one of the things
they must do is to select an article touched by their handler from a group
of similar articles. Then there's sport tracking, where the dog must follow
the trail of a stranger and identify an object dropped by that person. Many
search and rescue dog teams have started out in sport tracking and graduated
to real-life rescue work.
Here in Alaska there are three volunteer search and rescue dog groups: SEADOG
in Juneau, ASARD in Anchorage, and PAWS in Fairbanks. Tracking tests -- sport
tracking trials -- are held in both the Anchorage and Fairbanks areas. (This
year, the Anchorage area test is 95 miles up the Parks Highway on August
19, and the Fairbanks tests -- along with a seminar by Glen Johnson, who'll
be one of the Fairbanks judges -- are Labor Day weekend.)
Thus far, to the best of my knowledge, dogs in Alaska have not been involved
in detecting tiny pipeline leaks. But if a similar problem ever arises here,
we should keep in mind that these furry, four-legged biosensors, self-repairing,
self-propelled, user-friendly, and operating on renewable resources, have
demonstrated their ability to outperform modern technology at finding things
that smell.
Sue Ann Bowling wrote this article
over 20 years ago when she was training her dogs in sport tracking and attempts
to duplicate the abilities of a dog's nose have continued since. A
lot of the material (especially on the Ontario pipeline) came from a book
by Glen Johnson, "Tracking dog, theory and methods"
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