The dog nose arrived at my house in a box that said it contained a Corelle eighteen-ounce soup/cereal bowl. At the time, I had no idea what was actually inside. Gus barked the UPS truck good riddance while I checked the name on the return address. It was definitely not a bowl.
It had been weeks since Matthew Staymates, PhD, a fluid dynamicist and mechanical engineer with the National Institute of Standards and Technology (NIST), had said he would send me something interesting. It felt like Christmas in May as I drew the knife in a shallow track along the tape. The top of the box popped open like double doors to reveal a wad of crinkly brown paper. What could it be?
Gus was curious, too. He stood by me at the kitchen counter, his yellow Lab face smiling, his big brown eyes glancing from me to the package and back to me.
Open it! Open it! What did we get?!
I pulled away one corner of the paper, then the next. Something white and cylindrical peeked out. It looked like a cup. A cup? I ripped through the rest of the paper.
In my hands I now held a heavy-duty hard plastic replica of a dog’s nose. Not some cheap costume-shop version, but a 3-D-printed model of the exterior of a real dog’s snout, life-size. It was all white except for the soft black rhinarium (the cold wet part of a dog’s nose), with a perfect rendition of the nostrils, down to the little curvy slits on the side.
The inside of this particular nose was mostly hollow. It wasn’t anything like the intricate interior anatomy that makes a real dog’s nose such a superb sniffer. When I held it with the nostril end facing down, it looked like a strange Japanese teacup that would never balance on a table. “NIST” was written in it with a Sharpie.
From my interviews with Dr. Staymates, I knew he had created this nose himself on a 3-D printer. He used CAD (computer-aided design) files that had been supplied to him by fellow fluid dynamicist Brent Craven, PhD, who had created models of the complex inside of this same dog’s nose.*
Compared with Dr. Craven’s model, this nose was simplicity itself. And yet even this simple structure has been shown to vastly improve detection of odors when applied to a “sniffing” system. When Dr. Staymates and his colleagues used a similar design on a vapor detection system and had it mimic the way dogs sniff—inhaling and exhaling about five times a second rather than just drawing in air—vapor detection improved sixteen-fold.
This kind of canine biomimicry, when put to use with technology that already exists, could have far-reaching effects for future scent detection. As Dr. Staymates and his colleagues wrote in Scientific Reports, “These lessons learned from the dog may benefit the next-generation of vapor samplers for explosives, narcotics, pathogens, or even cancer . . .”
The mere shape of the outside of a dog’s sniffer can lead to possibly lifesaving technologies? This was my cup of nose.
I’ve been writing about dogs for thirty years. It’s been a joy to be able to focus part of my journalism career on these loyal, fun, intelligent, beautiful creatures. And now is an especially exciting time to be writing and reading about dogs. Never has there been so much interest in the hearts, minds, and noses of dogs as there is today.
As I wrote this book, I kept the nose on an empty corner of my large desk. It stared at me with its soft plastic nostrils, cheering me on and reminding me of a key theme at the core of the book.
Dogs can smell in parts per trillion. Craig Angle, PhD, codirector of Canine Performance Sciences at Auburn University’s College of Veterinary Medicine, likens this to being able to sniff out a teaspoon of a chemical in a million gallons of water—or the equivalent of nearly two Olympic swimming pools.
Our own sense of smell is much better than most of us think it is. But we’re limited. Dogs have a big advantage by virtue of their olfactory anatomy. We have about six million olfactory receptors in our noses. Dogs have up to three hundred million. They sniff in 3-D, with each nostril sampling air separately, which helps them locate a scent. And the brains of dogs are better equipped to make sense of the scents.
Yet as good as they are, dogs don’t rank among the best sniffers in the world, at least when measuring olfactory receptor genes. In a Japanese study of thirteen mammals, African elephants had twice as many functional olfactory receptor genes as dogs. Also ranking above dogs were rats, mice, cows, and horses. Humans placed just barely above other primates, which had the lowest number of genes associated with smell in the study. The researchers didn’t include bears, which are known to have a phenomenal sense of smell. Sharks and other nonmammals known for their olfactory abilities also weren’t part of the study.
Even if canines aren’t the olfactory superstars of our planet, they’re top dog when it comes to working alongside us to detect scent. They’ve long been our faithful assistants for jobs like explosives and narcotics detection, search and rescue, hunting, human tracking, bedbug detection, sniffing for cell phones in prisons, and rooting out certain foods from luggage at airports.
They’ve recently been helping humans in unprecedented ways. The list of jobs involving a dog’s sense of smell continues to expand as training techniques and our knowledge of dogs improve.
Dogs are searching for the feces of several species listed as vulnerable, threatened, or endangered, including orcas, tigers, giant anteaters, jaguars, and certain bears and wolves. This helps conservationists keep track of everything from the populations of these animals to their illnesses and diets. Dog noses are also tracking down water leaks in Western Australia, rhino poachers in Africa, cremated remains,* old bones of interest to archaeologists, elephant tusks, counterfeit money, and ancient artifacts.
And recently dogs have been using their olfactory skills on something that might prove most important of all: our health. Scientists and top-notch trainers are working together around the world to help canines help us with some of our biggest health concerns—everything from early cancer detection to diabetes control to stopping the spread of deadly bacteria. The dogs in this book are on the cutting edge of science.
Some of these coveted “biodetection” dogs work in homes, as service dogs. Others are regular pets whose people bring them into training centers and laboratories (which are truly fun places) to help researchers uncover the scents of disease. Most of the dogs in this book rely on their noses for their jobs, although many of the service dogs use a variety of senses.
Traditional service dog jobs like guiding the blind and helping the hearing impaired will always be in demand. But the world of the new “doctor dogs” is using the talents of dogs in ways we never would have dreamed of at the beginning of this century.
Some dogs use their noses for a living.
Gus smells for a living.
There is a difference.
It seems to be Gus’s calling to want to become certain scents. Or at least to wear them in style. If he really likes something, he’ll do his best to get it all over his body. This is usually accomplished by rolling in the scent, or at least sliding into it with his head and shoulders.
Gus is selective about the substances he likes to wear. They’re usually one of two categories: poop or dead animals. He will roll in grass, like normal dogs, but only if it has a specimen from one of these categories.
Sometimes he also goes for urine. In Golden Gate Park, we often pass by the police horse stables on our walks. Lately we’ve been coming across mounds of used straw near the corral. The first time we encountered one, Gus sniffed the air and dived into it, joyfully rolling and scratching his back for a few seconds, standing up, and crashing into it again.
I laughed to myself about him having a literal roll in the hay. But Gus got the last laugh, because as we continued our walk, I noticed a wretched stench—like used diapers festering in a bin. I sniffed and looked around for the source because I couldn’t shake it. Then I realized it was emanating from the bouncy, grinning Labrador retriever, and the stink was old horse urine.
Why, Gus, why?
I later learned that some wolves like to roll in the poop of carnivores such as cougars or black bears. And gray foxes seek areas frequented by male mountain lions and rub their faces in it. Could it be a form of camouflage? Some researchers think so. Others think it might be a way of carrying the odors of their journey back to the pack—kind of like the canine version of Instagram or Facebook.
Maybe. Or something else? On a sunny mid-February hike along a rugged leashes-optional coastal trail about fifteen minutes south of home, Gus cantered off ahead about twenty feet and threw himself down into something I couldn’t see. When I caught up with him a few seconds later, he had just completed a thorough body rub on his left side.
“Gus!”
He stood up and looked at me.
Yeah, I know, can you believe I found this? It’s so great, isn’t it?!
I looked where he had been rolling and saw what had lured him. It had the familiar shape of feces, but consisted primarily of a former animal, or part of one. It was hairy, twisted, and dark gray.
Coyote poop.
Gus beamed. He held his head high and wagged his tail in the same proud way he does when gets a new bone or ball. It struck me that he felt like he was now part coyote (not that I read into my dog’s behaviors or anything).
A little way down the trail, as I was admiring the ocean view, he plowed to the ground again, left shoulder first. This time it was a pile of fresh horse manure. When I stopped him, he stood up and seemed just as thrilled as he had with the coyote-poop incident. Now he was part horse, part coyote, and part Gus.
As we came to other dogs on the trail, he approached them in a different manner than normal—still friendly, but with a check ME out vibe. Sure enough, the dogs would run up to him and sniff Gus—this multi-animal wonder. They lingered on his left side, where he apparently smelled of both horse and coyote. (Thankfully, unlike during the horse-urine incident, his odor wasn’t obvious to the human nose.)
The older dogs would move along after a good inspection, but the younger dogs followed him around, sniffing more, wagging fast—clearly in admiration of this cool guy. He seemed to revel in the attention, walking slowly by them and standing with his left side for them to ogle again with their noses.
When we got home, the hose came out and washed away his hard-won glory.
I’ve often wondered if Gus could be a detection dog of some sort if he had the training. He’s only three years old, and he has the nose for it, a high drive for a reward of food or a ball, and he enjoys learning new skills. But what kind of detection would he do?
For personal reasons, it would be handy to me if he could be a cancer-detection dog. Even just a self-trained one.
When it comes to cancer detection, I have a dog in this fight—skin in the game. Or, actually, body parts in the game. In 2001, after a lifetime of radiant health, my amazing mom, Evelyn DeMagistris Goodavage, was diagnosed with stage IIIC ovarian cancer at age sixty-eight, seemingly out of the blue. A large mass was discovered during a routine annual checkup. There had been no sign of anything amiss during her previous exams.
Less than two years later, after two massive surgeries, chemotherapy, and a cruise through the Panama Canal, Mom was gone.
I would later discover that a few relatives on the Italian side of the family died from this cancer. I did the genetic tests my doctor recommended, and nothing came up as positive. But the geneticists still think I’m at high enough risk for the disease that I should consider preventative surgery. This is not something I want to have to do.
The problem is that, as with several other cancers, there’s no good early screening for ovarian cancer. The American College of Obstetricians and Gynecologists issued a statement saying, “Unfortunately, the existing evidence does not support any test to effectively screen for ovarian cancer. More research is still needed . . . [A]t this time, there is no effective strategy for ovarian cancer screening. Available ovarian cancer screening tests . . . are neither accurate nor reliable to screen asymptomatic women for early ovarian cancer.”
Ovarian cancer is known as “the silent killer.” Often there are no symptoms, or if there are, they’re so common—like bloating, indigestion, and lower back pain—it’s easy to attribute them to something more benign. As a result, most cases of ovarian cancer are found in later stages, when survival rates are low. It’s the fifth-leading cause of cancer deaths in women in the United States.
Living without a cancer safety net can be unnerving. I try not to think about it. But in the beginning of researching this book, I drove up to the In Situ Foudation, in Chico, California, to meet with Dina Zaphiris, a dog trainer who was involved in one of the earliest studies using dogs to detect cancer. And I did something I’m embarrassed to admit.
Dina’s star dog, Stewie, an Australian shepherd, has been trained to detect the presence of breast and ovarian cancer in laboratory samples. As you’ll see throughout the book, scientists think that dogs who detect cancer and other diseases or conditions may be picking up on volatile organic compounds (VOCs).
In a nutshell, VOCs are chemical substances released into the air. They can be natural or man-made. You may have heard of this term in relation to paints or solvents, but scientists reported in the Journal of Breath Research that they detected 1,840 VOCs in healthy humans. (They considered breath, saliva, blood, milk, skin secretions, urine, and feces.) Dogs like Stewie seem to be able to detect disease-specific VOCs.
Stewie is just a regular dog most of the time, enjoying a hearty belly rub or a chase around the pasture as much as any canine. But Dina explained that sometimes Stewie finds it hard to find the “off” switch outside In Situ’s research facility—a pleasant farm-style building on the outskirts of town.
Stewie sometimes approaches people on her own, sits down, and paws at them repeatedly—much as she would do with a cancer sample in the laboratory. Dina tries to discourage this and moves Stewie along. But she said it’s something Stewie seems compelled to do.
This puts Dina in a tough spot. Could Stewie be smelling cancer? Should she let the person know the possible significance of Stewie’s pawing, just in case? She told me she’s been hesitant to say anything, but if the situation allows, she will sometimes mention Stewie’s line of work. On several occasions, she’s learned that the person Stewie sought out does have cancer. Still, Dina doesn’t like to assign any status to Stewie’s occasional moonlighting.
“It’s not at all scientific. There are so many factors at play,” she says. “These dogs are trained on samples, not people.”
I couldn’t wait to meet Stewie, in part because this would be my first in-person encounter with a biodetection dog for this book.
There was another reason for my excitement. But I couldn’t tell Dina. She’d never approve. This had to be between Stewie and me.
On a sunny winter afternoon, I pulled into the driveway of In Situ’s training center. Dina was busy wrapping up a session, so an assistant came out to greet me. At her heels was a fluffy Australian shepherd. Stewie! I was in luck.
As Stewie trotted closer, I could see that one of her eyes was brown, the other half light blue and half brown, almost right down the middle. She held me in her gaze, her striking eye taking me in, her nostrils doing a little jig. I held my breath and steeled myself, with only one thought.
Please do not give me your paw.
My hope is that one day dogs will lead us to early detection of all kinds of cancers for which there is no “gold standard” test. But for now, just this once, I had an impromptu appointment with a talented early pioneer in this field.
To my relief, Stewie did not paw at me. She rolled over for a belly rub, then sidled close for a snuggle and ran off to greet another visitor. I realize her lack of signaling meant nothing and wasn’t based on science in the least. But still, it felt reassuring.
Gus may never be a cancer-detection dog, but he enriches my life in so many ways that I’m sure I’m healthier for it. When I’m having a bad day, I can talk to him and he’ll listen. Always. He loves me when I’m on a tight deadline and look like the Creature from the Black Lagoon as much as he does when I’m my more kempt self. (At least he pretends to.) He makes sure I get out in fresh air for long walks. He’s always good for a snuggle. He’s by my side when I take sick. And he makes me laugh.
Of course, he’s not perfect. He’s the reason the plastic nose now sits on a shelf instead of my desk. One afternoon I came home from the gym and he greeted me at the front door with something in his mouth. He always brings people gifts upon their return, so this was no surprise.
“What did you get me, Gus?”
He fast-wagged in joyful circles. I saw a flash of nostrils.
Not his nostrils.
“Drop it.”
He stopped prancing and opened his mouth. The hard plastic nose thudded to the floor, landing nostrils up.
I rinsed off the slobber and placed it on a shelf above my desk. Gus can’t reach it and doesn’t seem to care about it anymore. He’s been there, done that.
Most of the doctor dogs in this book go through extensive training to do their jobs—the canine version of medical school, minus student debt. It can take years to get seizure dogs or cancer-detection dogs ready for doing their precision work. But some rare dogs—clever pets—just wing it, somehow figuring out what’s amiss at home and telling their people about it as best they can.
While trainers and scientists from around the world spoke different languages and were working toward unique goals, they all had approaches that respected the dogs as collaborators. The training was all carrot, no stick. Rewards of toys and sometimes treats were given with love and enthusiasm. If a dog missed something in training, no biggie. The dog didn’t get the reward but was encouraged to try again.
With rare exceptions, the dogs I saw seemed to be crazy about their jobs. Those who work as service dogs were profoundly devoted to their mission and their people. The dogs who go to research centers to find disease in laboratory samples were equally excited about their work. They approached their tasks with the kind of focus and enthusiasm that managers wish their employees would have.
As I traveled, I interviewed dozens of people and watched their dogs at work. Whatever the culture, dogs smoothly, happily fit the needs, emotions, and lives of their humans.
In Japan, mobility-assistance dogs are sometimes trained to open packets of chopsticks and help pry them apart for people with limited hand mobility. Some can unwrap rice balls. Naoto Anzue, paralyzed from the chest down, drove me around Tokyo with his ultra-chill service dog, a yellow Lab named Dante. Dante flanked him as we ascended Tokyo Tower, had no fear of looking down the dizzying heights, navigated packed elevators calmly, and was a perfect gentleman as we later toured Edo Castle—better than some of the tourists.
In Amsterdam, I watched guide dogs learn to navigate the dizzying lanes of bicycle traffic. With more than 880,000 bikes in the city—four times the number of cars—it’s easy to stumble into bike territory if you don’t know what you’re doing. The dogs were brilliant.
In Croatia, I witnessed a beautiful service dog—a happy golden retriever named Freddi—as he balanced the needs of the twin teenage boys in his care, no matter what the weather, the pressures of school, or the boys’ condition. Leone and Renato Brašnić have had cerebral palsy since age two. Freddi helps them with some mobility issues and always seems to know when they’re sick—even before they know. The night before one of these bright, personable boys shows symptoms, Freddi will snuggle up to that boy and stay near for the duration.
“The medicine Freddi brings our family goes so much beyond the job he’s trained to do,” said their mother, Zeljka. “He fits our family perfectly and fills our souls with such happiness.”*
This book is divided into three parts. In the first section, you’ll meet dogs who are detecting cancer and Parkinson’s disease, and dogs who alert their people to seizures, diabetic lows or highs, and other life-threatening physical ailments. The second section features doctor dogs who are stepping into new fields such as sleep disorders, and even protecting us from antibiotic-resistant bugs and potential epidemic catastrophe. In the third part, we’ll look at the dogs helping people who are struggling with debilitating mental health problems such as anxiety, depression, schizophrenia, and post-traumatic stress disorder in its many guises.
The service dogs in this book are top dogs. They perform their jobs exquisitely. I don’t write about dogs with such poor training that they’re little more than glorified pets, and I don’t go into the stories of people who have spent a fortune on those dogs. But it happens, and it’s heartbreaking. There are well-meaning trainers out there who may not be producing great dogs, and there are some organizations that are considered moneymaking scams. Please do your homework diligently if you’re in the market for a service dog.
I also don’t get into the minefield that is service dog law and “fake” service dogs. This book is about dogs and what we are learning from them. It’s not about law. I’ll leave that for others to tackle.
But there will be a few cats. Cats have refined senses of smell. One study showed they might beat dogs in a couple of olfactory traits. As befits the feline stereotype of independence, cats who have alerted their people to health problems weren’t trained by anyone. They figured it out for themselves. So far I haven’t heard about any cats who have been taught to detect human illness, but cat experts think that with early socialization and training, it could well happen. In which case, my next book will be called Clinician Cats.
They’d be joining a growing parade of other animals already ensconced in the biodetection field. African giant pouched rats (surprisingly cute critters, known for their brains and trainability) do an excellent job rapidly sniffing sputum samples for tuberculosis—one of the top ten causes of death worldwide.* Mice have been trained to detect bird flu in duck poop. Genetically modified fruit flies can accurately detect breast cancer cells using their olfactory senses.
Even worms seem to be able to detect cancer. While in Japan, I spent some time at Hirotsu Bio Science outside Tokyo. Researchers there are developing a cancer-screening method based on their finding that nematodes can detect the smell of cancerous cells. I watched as several wee worms waggled their way toward a dot of urine from someone with cancer, and away from a dot of urine from someone without cancer. The race to the mini pee pool took place in a petri dish. To the naked eye there wasn’t a lot of action. But as I stared through a microscope, it was clear that these were worms with a mission.
I wanted to interview them and ask them just one question: “Why?”
It’s a question I don’t have to ask doctor dogs.
“These working dogs share a tight emotional bond with their handler. Consequently, they find working together with a person they love tremendously satisfying,” says Clive Wynne, PhD, a behavioral scientist who directs the Canine Science Collaboratory at Arizona State University. “In modern working dogs we see the powerful connection that underscores everything about dogs’ lives with us.”
Could it be love?
The scientific jury is still out on whether dogs truly feel love. Some canine cognition experts say yes, dogs do love us. Others are careful not to ascribe such an emotion to them. This book leans heavily on science, but rather than try to sort this out logically and academically, I will come right out and admit my bias: Of course dogs feel love. And if you’re holding some shredded chicken in your hand, all the better.
I asked Dr. Wynne for his opinion. He answered: “I think the secret to dogs’ success with people is their extravagant capacity for forming strong emotional connections with members of other species. In my scientific writing I call this ‘hypersociability’ or ‘exaggerated gregariousness,’ but it is the same thing that laypeople simply call love. Love is the essence of what makes dogs who they are.”