by Cat Warren
The media appear to know a lot about dogs finding the dead. The problem is that stories are scattered everywhere, hundreds and thousands that all have the same innocuous story line: A person walking a dog finds a body. I am convinced that an analysis would show that untrained dogs out for walks or roaming neighborhoods find more bodies than trained dogs do. It’s a simple question of acknowledging the millions of dog noses out there working unpaid overtime.
Depending on your perspective, it’s either good or bad to let your dog roam off-lead, but let’s face it: Dogs on leads don’t find bodies nearly as often. Generally, finding a body is a good thing, although the dogs’ owners and walkers are never thrilled when it happens.
Ollie, a golden retriever, was in Hollywood Hills on an unleashed walk in January 2012. A professional dog walker and her mother had eight other dogs with them. Ollie dashed into the underbrush and started playing enthusiastically with a plastic bag: “He was digging, digging, digging, barking,” the dog walker, Lauren Kornberg, told the local radio station. Ollie shredded the bag and came away with something big and round in his mouth. He dropped it, and it rolled into a ravine. Kornberg admitted that it was her mother, “a responsible adult,” who went to investigate—and found the head that Ollie had dropped.
A four-year-old black Labrador named Fish brought a decaying human arm into the front yard of his Mission, Texas, home in August 2011. Police were able to get the hand and arm bone before they disappeared down Fish’s throat. The dog’s adult owner was traumatized. Not so his eight-year-old daughter, who chatted with the television reporter. Their dog, she said, likes to visit the neighbors’ chicken coop as well: “Fish gets everything. He brought eggs on Easter.”
I understand her father’s repulsion. I wouldn’t accept Fish’s gift of eggs.
When dogs become, in Paul Shepard’s term, “the spoiler of human graves,” it’s a reminder of how we tend to deal with human bodies. We Westerners tuck them away fairly quickly. Dogs like Fish remind us of the disorder and chaos inherent when there’s an arm or hand lying around where a dog can find it. We prefer hands either made into sterile ash or nicely preserved with formaldehyde and gently crossed over the body in a coffin. On the flip side, turnabout should be fair play. Both historically and in current practice across the world, people eat dogs without much compunction. There’s good evidence that dogs were and are raised for meat; they were the first agricultural animal in a number of societies, and they remain so in some today.
None of my early research on cadaver dogs grossed me out. I realized there was a difference between reading about it and coming face-to-face with it, but abstractly, the idea of cadaver-dog work didn’t offend my sensibilities. It made me happy. Perhaps my childhood in the woods and fields, growing up with fishing and hunting and gutting and plucking and skinning, was a factor in my sanguinity. Or the fact that I had taken care of my paralyzed mother and worked in nursing homes for years. Perhaps it was because my father was a biologist who taught me to look at dead organisms with a disinterested but not uninterested gaze.
Cadaver-dog work seemed straightforward to me. As one medical examiner and early cadaver-dog trainer, Edward David, noted with great cheer, “love of the putrid” is inherent in canines. So why not take that love and channel it toward something more socially useful than rolling in dead squirrel?
Why not take that love and see whether it might be used not to increase the chaos but to restore, even if only slightly, a sense of order?
3
Nose Knowledge
There are seventy-five perfumes, which it is very necessary that a criminal expert should be able to distinguish from each other, and cases have more than once within my own experience depended upon their prompt recognition.
—Sherlock Holmes, The Hound of the Baskervilles, 1902
These days, when I watch a good dog work scent, I can see him trace its passage in the air until he’s drawn a clear picture with his nose. An experienced dog can illustrate the difference between scent that has lifted in the heat of the day, settled down in the ridges of rough grass, or been pulled hard toward the rushing water of a creek.
I work scent also, though I don’t run as fast or as hard. I can recognize urine in the muggy concrete stairwell of a parking garage, mildew liberated from under sheaves of rotted leaves, and the fishy musk of a German shepherd after a swim in the Eno River in August.
I knew, even before I started researching dogs’ noses in a sustained manner, that they were much better than humans’. Solo’s was much better than mine. David could use a pair of scissors on a package of vacuum-sealed meat in the kitchen, and the silent exhalation of bloody air would wake Solo and bring him running from across the room. Conversely, it seemed lazy to concede that dogs are the masters of the domain of olfaction before I’d done any scientific fact-checking. Sure, Solo has a bigger nose than I do, but size isn’t everything.
So what’s the truth about dogs’ sense of smell? I don’t want to keep the reader in suspense: The truth is, we don’t know that much about it. As I began researching, I noticed wildly fluctuating figures in both the sentimental and scientific dog literature: The dog’s nose was either ten times or a hundred times or a thousand times or tens of thousands of times better than the human nose. Those figures raised doubts. If scientists, or people who play them on YouTube, or your basic dog lover had stuck with one false figure—say, that dogs’ noses are a thousand times better than ours—or if they had stated the figures with less certainty and more modesty, I might not have become suspicious. Given the variation, I wondered, how much better are dogs’ noses, really? And if they are better, what are they better for, exactly? Sniffing dog pee?
In tracking rumors, as with tracking most things, it’s good to start at their genesis. There’s a growing body of scientific evidence suggesting that not only have the nose and its receptors been important to the survival of creatures for at least hundreds of millions of years; they may also have been a key evolutionary force driving the growing intelligence of mammals.
In 2011, Texas paleontologists published their analysis of the skulls of pre-mammals living 190 million years ago. Their research shows that one of our pre-mammalian ancestors, the Hadrocodium wui—a shrewish beast with a skull smaller than a paper clip—didn’t have the option of rejecting smells. It tremulously ventured forth to sniff for grubs and insects, probably at night so the diurnal dinosaurs didn’t accidentally squash it. Its fur was important, its twitchy ears important, its vision important. But, the paleontologists argued in Science, it was the critter’s olfaction system that was the most impressive thing in that bitty skull: “[It] differed from even its closest extinct relatives specifically in its degree of high-resolution olfaction, as it exploited a world of information dominated to an unprecedented degree by odors and scents.” They theorized that these skulls showed the olfactory system played a major role in helping the mammalian brain evolve, apparently to the point that we humans—the most advanced of mammals—could turn our collective nose up at thinking too much about smells.
We should feel grateful to the tiny Hadrocodium wui, fossilized and preserved in China, for helping us understand the importance of a sense of smell. Yet there’s still much about this sense that scientists don’t know. It was only recently that researchers started to decode how our olfactory system actually works. Thanks to Linda Buck and Richard Axel, who won the Nobel Prize in 2004, we’ve learned that when a volatile aroma latches on to an odorant receptor, it fires an olfactory neuron. Bam. That is not the only theory out there, but it’s the reigning one. You would think that researchers would be further along in understanding this particular sense, but amid the general devaluing of the sense of smell in the Western world, the chemical complexity of odors, and the complexity of the neural circuitry that underlies even the act of sniffing, they have a ways to go.
As for comparing one nose with another? Neurobiologists aren’t that interested in setting up olfaction competitions between specie
s. They don’t care which species’ nose is “the best.” What does that mean, in any case? This kind of speculation is better left to Animal Planet’s Creature Countdowns, featuring the “Top 10 Animal Troublemakers” and “Top 10 Animal Skills.” The bloodhound made number nine on that last list, with a sense of smell so fine, according to the producers, that it is “up to a million times more sensitive than that of humans.” I am not making this up. Animal Planet is.
Some species’ noses do rise above the rest, literally and figuratively. I bet if we could train bears to track, their noses would confer real bragging rights. Biologists believe that grizzly bears generally have a much better sense of smell than any dog. Bears’ noses get less press than dogs’ for all the obvious reasons. If you ever get the chance to stare at a grizzly’s nose close up, you can see what a stunning instrument it is—tilted up at the end, with huge flaring nostrils. If you are at exactly the right angle, you can see through that nostril space to the blue sky beyond. The grizzly bear can manipulate her nose like a flautist can flex her fingers. If you could peer inside her horribilis skull at the nasal cavity, you would see delicate structures that look like two huge morel mushrooms or rounded honeycombs planted side by side. Their job is to process scent. How well? Pretty darn well. For miles, it’s estimated.
But maybe not for miles and miles and miles. Nonetheless, Animal Planet, some books, and a number of bear websites use the following phrase: “Some scientists say bears can smell carrion from up to 18 miles (29 kilometers) away.” It’s rather odd, I thought, that “some scientists” would all agree on such a specific bear mileage. The figure’s genesis, I discovered, was one 1976 bear-conference paper noting that one radio-tracked bear traveled twenty-nine kilometers with some speed and ended up at a carcass. The ecologist, Frank Craighead, stipulated, “It was not determined just when and how the carcass was detected.”
Nor are there good comparative studies about the capacities of one animal’s nose versus another, said Larry Meyers of Auburn University College of Veterinary Medicine. Repeat falsehoods enough, though, and they don’t just take on the patina of truth, they become its replacement. Bears don’t care, and inventions about their olfactory capacity probably matter less because bear handlers don’t end up testifying in criminal court about their abilities. Nor are bears’ noses depended on for finding lost children alive.
Besides, there’s just no great bear-nose grant money these days. The same isn’t true for research on human noses. We’re always interested in ourselves, and it’s easier and safer to get human noses, rather than bear noses, into a laboratory. Even while we tend to denigrate it, the human sense of smell is getting more deserved attention. Humans can detect thousands of different odors. Even Linda Buck, Nobel olfactory biologist par excellence, hems and haws over some details: “It is estimated that humans, for example, can detect from 10,000 to over 100,000 different volatile compounds.” That’s a difference of a factor of ten, less than some of the variations I’ve seen used with dogs, but hardly a rounding error.
While smell isn’t entirely a lost subject for research or practice, for most Westerners, it is a deeply underappreciated sense compared to vision. It wasn’t always so. Smell used to be a critical tool for physicians. Hundreds of years before we started exclaiming over the miracle of dogs being able to detect diabetes or lung cancer, doctors were using their noses to do the same thing. “Evaluating effluvia” was considered a basic diagnostic skill: Sweat on a rubella patient smelled like “freshly plucked feathers”; life-threatening diabetic ketoacidosis made a patient’s breath smell like “rotting apples”; a certain bacterial condition made the skin smell like “over-ripe Camembert.” Now we leave that job to lab tests and litmus paper.
Vestiges of human scent skills do survive in pockets in the West. For instance, “odor mitigation” expert Larry Sunshine will fly into a city, tilt his head, open his nostrils, and identify specific foul odors in subways, including mildew and chemicals venting off plastic seats. Luca Turin, a perfume expert and biophysicist, can deconstruct a perfume down to its exact compounds and describe it in terms that make you want to laugh and weep and even buy that particular patchouli: “The smell was at once beguiling, salubrious, and toxic, and felt like a perfume composed for a fiercely intelligent librarian.”
Research is starting to blossom in this world of human olfaction, and it’s taking some interesting turns—ones that working-dog handlers can relate to. Certain scents turn humans into the kinds of tracking machines whose accomplishments seem to rival those of trained scent dogs. If chocolate is involved. Scientists took a group of Berkeley undergraduates, showed them a video of canine scent-tracking, and then took them out on a lawn that had been laced with essential oil of chocolate. Scientists gave the students blindfolds, thick gloves, knee and elbow pads, and let them loose, off-lead. Could they track the chocolate using their noses, crawling on their hands and knees? Absolutely. The track they followed looked like the zigzag of a dog’s trail.
The Berkeley scientists loved the students for more than their noses. Unlike rats or dogs, they could be debriefed afterward. The students could even say which nostril they tended to depend on: “Humans are an appealing animal model for addressing such questions because they can follow task instructions and accurately report behavioral strategies,” noted the article in Nature Neuroscience.
Fortunately, that’s one aspect of olfaction that a few researchers are starting to focus on moving forward, both in humans and in dogs: the importance of training. Olfactory scientist Avery Gilbert has long argued that the trained human brain processes and understands scent differently. “I’d like to challenge my academic friends to stop giving random orders to college sophomores in the psychology labs,” he wrote, “and start observing odor fluency where it happens naturally—in creative people actively engaged in smell.”
In that respect, water is like chocolate. University of Pennsylvania researchers concluded in a study on people’s ability to taste water that training, more than anything else, most enhances people’s ability to identify smells. And during a repeat chocolate-tracking trial in Berkeley, students cut their tracking time by nearly two thirds. They learned to sniff faster. The students, taken out of the classroom and placed on grass, started to develop working noses.
• • •
Abalone and accelerants. Termites, truffles, and TNT. Crack cocaine and citrus cankers. Mildew, moths, melanoma. Peanut butter, pythons, and people. Spotted owls and spiny lobsters. Cows in heat. Gas leaks.
If there’s a particular smell out there—illegal, endangered, delicious, destructive, invasive, or dangerous—handlers will try to train dogs to find it. The list of smells is lengthening daily.
Using hunting dogs who use their noses dates back many thousands of years. Human tracking and avalanche-rescue work originated centuries ago. But the explosion of tasks we’ve found for dogs in the past four decades often reflects our all-too-human tendencies toward violence, addiction, arson, and excess. We have entered the era of the sniffer dog.
Working-dog historians may argue about when that era began. The first handful of U.S. police-dog programs were developed at the turn of the twentieth century in New York City and New Jersey. Over the next few decades, units emerged in Connecticut, Berkeley, Pennsylvania, and Detroit. Fewer than twenty programs existed up through the early 1950s. After that, police K9 units reproduced rapidly.
Much of the expansion coincided with the military’s experimental animal science that began in the mid-1960s and lasted into the early 1970s, during the Vietnam War, when researchers realized that sentry and scout dogs could be trained for additional sniffing tasks: finding punji pits and trip wires, not to mention illicit drugs in soldiers’ barracks in Vietnam. On the domestic front, the military-research scientists speculated that dogs might be used to find bombs and weapons. Hijackings, bombings, and assassinations were on the rise in the United States: what one researcher called “the ills of the 1960s.”
It
wasn’t just in law enforcement that the uses of dogs’ noses started multiplying. Seattle area trainer and handler Marcia Koenig, one of the early volunteer search-dog team members, tracks the history of volunteer search-dog teams to 1962, when the German Shepherd Dog Club of Washington State formed the first air-scenting search-dog group. One of its founders, Bill Syrotuck, wrote the clear, concise book Scent and the Scenting Dog (one of the books Nancy Hook had permitted me to read). Today volunteer groups deploy to search in wilderness areas, in avalanches, on water, and in disasters. Marcia Koenig estimates that the U.S. has more than five hundred volunteer teams.
While working dogs were off and running by the mid-1960s, it’s best not to feel too sentimental about what that growth represents. Each time a dog accomplishes a particular task for humans isn’t automatically a moment for celebration. Dogs may have co-evolved with us, but they don’t have a lot of say in how we decide to use them, so the “co” gives a false impression of equity. The dog mostly tries to please us, using its “canid tool kit of flexible sociality, a good nose, and expertise in hunting,” as John Bradshaw, Foundation Director of the Anthrozoology Institute at the University of Bristol, puts it.
Good working dogs have to move swiftly, hear acutely, smell well, and communicate clearly with their handlers—even bite on occasion. Since domestication, they’ve been used as adjuncts for the evil that people do, as well as the good, and sometimes both at once. They can be used to consolidate or pervert power in concrete ways. They can track a slave, a lost child, or a rapist without distinguishing. They can help suppress peaceful civil rights protesters or control an angry mob that’s up to no good. People create the problems, and working dogs come along for the ride. Right now, as we engage in conflicts in the Middle East and South Asia, we use dogs to find bombs and control the groups fighting against us. When domestic boas and pythons get too big for Florida apartments, they are dumped in the Everglades, and we use dogs to locate them before the snakes decimate the native wildlife. We have huge prisons filled with contraband and cell phones, and we use dogs to find them.