Former Marine Sergeant Brandon Liebert, whom you may remember from an earlier chapter (his dog, Monty, found six hundred rounds of antiaircraft ammunition), was stationed at Cherry Point, North Carolina, in 2005. One day he sent out a dog team to sweep the convention center in Morehead City prior to a Marine Corps Ball. The team went out on what was a formality. But a few hours later Liebert received a call to say that the dog had responded to something in one part of the convention site. Verification was required. Liebert was the only handler available, so he got Monty and rushed off to investigate.

"When we got to the area of where the other dog had responded, Monty began to circle the room multiple times and then finally stopped in the middle of the room. I asked the handler what his dog did, and the handler stated that his dog had responded on the tables behind me. We got out of the area and informed the local authorities." dog did, and the handler stated that his dog had responded on the tables behind me. We got out of the area and informed the local authorities."

It would later turn out that there had been a Ducks Unlimited show the previous weekend and that there were a lot of guns and ammunition for sale. The vendors had placed the ammunition on tables, and so it was a residual odor the dogs had picked up on. The ball went on as planned.

31

A TOUR OF A DOG'S NOSE

Not all dogs have the same genius for sniffing. Dogs with longer snouts generally have more sensitive noses than dogs with stubby noses, like bulldogs. This is one of the reasons why you will probably never see a pug as a military working dog, unless the military decides it needs something rather amusing-looking to distract the enemy.

Let's see why size matters. If you have more odor a.n.a.lyzers in your nose, you are going to be more sensitive to smell. We humans have about five million odor receptors in our noses. The area these take up if unfurled would be about the size of a postage stamp. Dogs with long noses have far more of these scent receptors. Dachshunds have 125 million. But German shepherds have 225 million of them. So do beagles, which is pretty amazing considering they're half the size of shepherds. Bloodhounds have the most, with three hundred million. A bloodhound's olfactory receptor area is about the size of a handkerchief. (You will not see bloodhounds in the military, though. Doc Hilliard explains that while they have great noses, and can be excellent trackers, most do not retrieve or play with Kongs or b.a.l.l.s the way they need to for the training. I wonder if another reason could be that their droopy, drooly countenances don't seem very "military.") noses, and can be excellent trackers, most do not retrieve or play with Kongs or b.a.l.l.s the way they need to for the training. I wonder if another reason could be that their droopy, drooly countenances don't seem very "military.") Smell is the dominant sense in dogs-even in those with less prominent snouts. From the outer nose (known as a dog's "leather") to the brain, a dog's olfactory system makes ours look like it needs to go back to the manufacturer. (But our eyes have all the grandeur of their noses, so it all works out.) Here's a quick look at what happens when a military working dog we'll call Sam, a German shepherd, sniffs an odor of interest; let's say ammonium nitrate. Sam is close to a scent, but not sure quite where it is yet. He sniffs more rapidly, so the air coming into his nose is more turbulent and more of it can be distributed onto his olfactory membranes. He can sniff up to twenty times for every exhalation if he's really interested in a scent. He can even pull a neat trick of inhaling at the same time he exhales. And he can move his nostrils independently, which helps him figure out just where a scent is coming from. When Sam thinks that he may be quite near the source, he will sniff more deeply, actively drawing air over the source to confirm its location. At this point he may even be able to compare the concentration of odor between left and right nostrils, which will both confirm that the source is nearby and further help to pinpoint its location.

As he sniffs, scent molecules stick to the moisture on Sam's nose. (The moisture is actually mucus, which helps snortle the molecules all the way through the olfaction process.) Scent molecules dissolve in the mucus, and the sniffing carries them into the nose, to two bony plates called turbinates. This is the home of those millions of scent-detecting cells discussed earlier. to two bony plates called turbinates. This is the home of those millions of scent-detecting cells discussed earlier.

Adding to Sam's nasal prowess is a body part that doesn't seem to exist in any functional form in humans: an extra olfactory chamber known as the vomeronasal organ, aka Jacobson's organ. It's located above the roof of a dog's mouth, just behind the upper incisors. It has ducts that open to the nose and mouth so scent molecules can be processed. Most mammals and reptiles have a vomeronasal organ. It's used primarily to detect pheromones (not terribly helpful for Sam on the job), but some scientists think it may have other functions we're not yet aware of.

The brains of dogs and people and most vertebrates contain two structures called olfactory bulbs, which help us decode smells. The olfactory bulbs of dogs are about four times as big as those of people, despite the fact that dogs' brains are far smaller than ours. Between this and his 225 million scent receptors, Sam is able to find the ammonium nitrate quickly. He sits, stares, and is called back by his handler, who gives him his cherished Kong and praises him up like mad.

All in a day's work for a good nose.

Oh, and lest you think it's all about sniffing and letting nature take it from there, a dog also has to do a great deal of legwork to locate an odor. Bradshaw explains that a dog's first strategy is to run cross-wind to figure out whether or not he is directly downwind of the source. But wind spreads scent in unpredictable ways, so this may not be very informative. If the scent is continuous, the source must be very close by, so the wind direction is an unreliable clue, and visual cues may provide the best indication of the source. If the scent is discontinuous, its source is probably some distance away, so the dog will briefly switch to proceeding upwind; if the scent is quickly lost, he will switch back to running cross-wind to try to position himself more precisely in the odor "corridor." Then, switching between upwind and cross-wind running will bring the dog, somewhat crabwise, to within close range of the source. scent is discontinuous, its source is probably some distance away, so the dog will briefly switch to proceeding upwind; if the scent is quickly lost, he will switch back to running cross-wind to try to position himself more precisely in the odor "corridor." Then, switching between upwind and cross-wind running will bring the dog, somewhat crabwise, to within close range of the source.

But what if the scent itself is moving?

32

A CLOUD OF SCURF

In the silence of the vast desert, you can hear the chop-chop chop-chop of the marine UH-1 helicopter (aka a Huey) approaching for miles. It comes near and veers suddenly, looping in quick semi-amus.e.m.e.nt-park fashion, circles overhead again, and descends. As it nears the ground, a fast-moving cloud of dust and tiny pebbles races toward Gunny Knight and me, dinging my camera lens and making it impossible to keep our eyes open for the next several seconds. of the marine UH-1 helicopter (aka a Huey) approaching for miles. It comes near and veers suddenly, looping in quick semi-amus.e.m.e.nt-park fashion, circles overhead again, and descends. As it nears the ground, a fast-moving cloud of dust and tiny pebbles races toward Gunny Knight and me, dinging my camera lens and making it impossible to keep our eyes open for the next several seconds.

The air remains thick with dust when out of the helicopter, whose rotors are still churning, run a dog and handler, followed by another dog team. The handlers hunch forward slightly as they run, to better protect themselves from the churning sand and air. They race off into the distance, then stop. The dogs sniff the ground with great interest, but just then the helicopter lifts off, and we lose sight of everything again.

Gunny and I catch up with these teams, and a few others, while they're resting up after having tracked a "bad guy" varying distances at the Yuma Proving Ground. The dogs are combat tracker dogs. While explosives dogs find bombs, these dogs find the people who plant them. (In friendly operations, they can track down lost people.) The dogs here today are training for real-life combat missions, which often involve these rapid helicopter drops. The dogs need to get used to these so they're ready when they deploy. dogs. While explosives dogs find bombs, these dogs find the people who plant them. (In friendly operations, they can track down lost people.) The dogs here today are training for real-life combat missions, which often involve these rapid helicopter drops. The dogs need to get used to these so they're ready when they deploy.

One of the dogs was so scared of the helicopter this day that he put the brakes on as he approached it and had to be nearly carried aboard. He spent the ride with his head tucked firmly into the crotch of his handler, who had to move her rifle to make room for him. (Once off the helicopter, though, he tracked his man beautifully, I'm told.) Most dogs stayed very close to their handlers, and hunkered down and strapped in, for the ride. One veteran dog took in the view from the helicopter's edge while firmly grasped by his handler.

These dogs are trained to track human odor over distances. They pick up a scent where a handler "suggests" (near an IED, for instance, or the last place an insurgent stood) and follow it. Tracks can be miles long and hours-or even days-old. Recall James Earl Ray, who broke out of a Tennessee prison in 1977 and was pursued by sister bloodhounds named Sandy and Little Red. They started their manhunt days after his escape, but within a few hours they had found him a mere three miles away. (Now there there are a couple of hound dogs who could do the job.) are a couple of hound dogs who could do the job.) Tracking dogs keep their heads down and follow the scent on the ground. The track is a combination of human scent and crushed vegetation or stirred-up dirt or sand. Disturbed environments, like crushed gra.s.s (the gra.s.s "bleeds," in a sense), give off unique smells. But nothing as unique as the smell of the person being pursued.

You may think that if you shower well and wear deodorant, you smell like just about everyone else out there. But our individual scent fingerprints are unique. As Horowitz says, "To our dogs, we smell like just about everyone else out there. But our individual scent fingerprints are unique. As Horowitz says, "To our dogs, we are are our scent." our scent."

Anyone who is thinking of outwitting a tracking dog one day should read what she has to say about our scents: Humans stink. The human armpit is one of the most profound sources of odor produced by any animal; our breath is a confusing melody of smells; our genitals reek. The organ that covers our body-our skin-is itself covered in sweat and sebaceous glands, which are regularly churning out fluid and oils holding our particular brand of scent. When we touch objects, we leave a bit of ourselves on them; a slough of skin, with its clutch of bacteria steadily munching and excreting away. This is our smell, our signature odor.

Coren likens our shedding skin cells to the Peanuts Peanuts character Pigpen, who always has a visible billow of dirt around him. It seems humans have the same billow, only it's made up of skin cells, which when in this flake form are known as rafts or scurf. We shed fifty million skin cells each minute. That's a lot of scurf. "They fall like microscopic snowflakes," Coren says. Thankfully, we can't see this winter wonderland ourselves. But these rafts or scurf, with their biological richness, including the bacteria that sheds with them, are very "visible" to dogs' noses. character Pigpen, who always has a visible billow of dirt around him. It seems humans have the same billow, only it's made up of skin cells, which when in this flake form are known as rafts or scurf. We shed fifty million skin cells each minute. That's a lot of scurf. "They fall like microscopic snowflakes," Coren says. Thankfully, we can't see this winter wonderland ourselves. But these rafts or scurf, with their biological richness, including the bacteria that sheds with them, are very "visible" to dogs' noses.

Where a dog begins on a track is naturally where the scent is weakest, because it's been there longest. As the track progresses in the right direction, the scent should get stronger. The increasing strength of a track is something dogs rely on. "They start at the farthest point in the past and work their way up, we hope, to the present moment, where they find who they're tracking," says Marine Corporal Wesley Gerwin, course chief/instructor supervisor for the combat tracker course. "It's sort of like a dog's version of time travel." strength of a track is something dogs rely on. "They start at the farthest point in the past and work their way up, we hope, to the present moment, where they find who they're tracking," says Marine Corporal Wesley Gerwin, course chief/instructor supervisor for the combat tracker course. "It's sort of like a dog's version of time travel."

Dry heat and ultraviolet light can cause a track to disintegrate quickly. Moisture and lack of sun help preserve tracks. Even if someone tries to throw a dog off the scent by going through a stream or river, there's still likely to be a track. In most cases, if the dog is not too far behind, the water will not erase the scent. In fact, breezes can waft a person's scent to a moist riverbank, where it can remain for a long time. (If a river is flowing very quickly and is relatively shallow, though, the scent dissipates far more swiftly.) There aren't many combat tracking dogs in the military. The numbers are in the low dozens, but security concerns preclude a more precise count. CTD handlers have to have been military working dog handlers for a minimum of a year; they then spend six additional weeks in a CTD course-four weeks at Lackland, two weeks at Yuma. The dogs are trained as combat trackers from the start. They begin tracking at distances of a foot or two (a second or two old) and work their way up. The oldest recorded track since the CTD program started in its most recent incarnation a few years ago is seventy-two hours, in Al Anbar Province, Iraq. Gerwin says he's heard talk of a track up to five days old, but it's not official.

33

DOG SENSE

In addition to their stellar noses, combat tracking dogs, like all military dogs, rely on other senses to do their jobs. Phenomenal as their noses are, soldier dogs can't go purely by scent. A combat tracker, for instance, will use his eyes and ears to pinpoint his target as he approaches it. Patrol dogs depend a great deal on hearing and eyesight as well, especially when it comes to detecting the subtle movements or sounds of a suspect.

Like their noses, dogs' ears are significantly more sensitive than ours, especially at high frequencies. "Dogs would describe us as having high-frequency deafness," writes Bradshaw in his book Dog Sense Dog Sense. In the Pacific Islands during World War II, soldier dogs could sometimes detect the thin wires on b.o.o.by traps by the very high-pitched whine produced when air moved over them. Some dogs ended up being trained in just this sort of sound detection. (The sound was utterly inaudible to any humans nearby.) Canine ears have a reputation of being able to hear sounds up to four times farther than ours can. The mobility of their ears plays a role in helping locate and focus on sounds. As anyone who has ever watched a dog listen to something of great interest will tell you, a dog's ears almost seem to have minds of their own. It's no wonder: Dogs have about eighteen muscles helping them swivel and tilt their ears in response to sound. It's pretty endearing to watch. Jake is adept at this ear maneuver whenever he begs for food or sits in the backyard listening for the cat. to four times farther than ours can. The mobility of their ears plays a role in helping locate and focus on sounds. As anyone who has ever watched a dog listen to something of great interest will tell you, a dog's ears almost seem to have minds of their own. It's no wonder: Dogs have about eighteen muscles helping them swivel and tilt their ears in response to sound. It's pretty endearing to watch. Jake is adept at this ear maneuver whenever he begs for food or sits in the backyard listening for the cat.

Dogs have poor color vision compared to ours, decent night vision, and generally see a wider picture than we do because of the placement of their eyes. But how a dog sees the world is highly dependent on what a dog looks like. Dogs with longer noses, like most military working dogs, tend to have more photoreceptors crowded together in a horizontal streak across the eye. This "visual streak," as it's called, makes for better panoramic vision, with a field of vision that extends up to about 240 degrees (as opposed to our full frontal 180). Dogs with this kind of vision can even have some awareness of what's going on behind them. But don't ask them to focus on anything closer than ten to fifteen inches in front of their noses. Their eyes aren't set up for that kind of vision. Dogs with shorter noses likely do better with closer vision. Their vision cells are packed in more of a circular shape, making for a narrower field of vision and more visual acuity up front.

This may explain why retrievers retrieve and lapdogs, with their big forward-looking eyes and their small snouts, like to sit on your lap and look at you.

Scientists are continuing to investigate the eyes, ears, and noses of dogs. And beyond the realm of these senses, they're reaching out to get to know more about dog psychology, including how dogs think, feel, solve problems, and why they behave the way they do. Canine cognition is a relatively new field that's burgeoning with enthusiastic scientists eager to plumb dogs' minds for things we've wondered about but never explored before. reaching out to get to know more about dog psychology, including how dogs think, feel, solve problems, and why they behave the way they do. Canine cognition is a relatively new field that's burgeoning with enthusiastic scientists eager to plumb dogs' minds for things we've wondered about but never explored before.

34

PLUMBING A DOG'S MIND

The heart of the Duke Canine Cognition Center is the dog lab. Unlike many laboratories that use dogs as guinea pigs for research, there is no pain in this lab. There aren't even cages. In fact, the lab looks like a small dance studio. The white floor is striped with an a.s.sortment of tape colors; red, green, yellow, and blue. The dogs who come here enter with their owners, stay within feet of their owners, leave with their owners, and inevitably get treats and lots of attention during the studies. It's Center Director Brian Hare's idea of "an awesome place to learn about dogs."

It's late morning, and Hare, a.s.sistant professor of evolutionary anthropology and cognitive neuroscience, warns me that he just had cake from Costco and a coffee. "I'm totally ADD, I warn you. I'm really excited about a lot of things," he tells me, blue eyes glittering. For the next hour, Hare talks fast and nonstop about the dog lab as he careens about his office. There's something about his energy, his look, and demeanor that keeps reminding me of Brendan Fraser's George of the Jungle-only Hare's rendition holds advanced degrees, has earned great respect in the world of academia, and has the tremendous responsibility that goes along with founding and running a major research facility at one of the nation's top universities. academia, and has the tremendous responsibility that goes along with founding and running a major research facility at one of the nation's top universities.

This lab is one of a few dog cognition labs that have opened at universities in the United States in the last several years, including one run by Alexandra Horowitz at Barnard College. Until the late 1990s, little attention was paid to the topic of canine cognition. Primates were the primary animals being studied for cognition. But "now it's like out-of-control exciting, trying to unlock the secrets of a dog's mind. Now everybody is so super-excited by this research on dogs, from psychologists to anthropologists to the average American dog lover," Hare says as he swipes his hands through his shock of thick, wavy hair.

Hare and his staff had just written a grant to the Department of Defense when I visited. He admits he's never worked with military dogs before, but he has many ideas about how his center can help advance the understanding of dogs in a way he thinks would benefit the military dog program. He'd like to develop a cognitive test for dogs who have been involved in stressful situations, like deployments. He also wants to be able to put together a system so handlers can check their dogs for stress in the field by methods other than simply looking at behavior. This involves testing cortisol levels in conjunction with core body temperatures, as taken by a thermal imaging temperature gun.

In addition, he'd eventually like to be able to use the results of an ongoing study on something called "laterality bias" to help improve accuracy of detector dogs. "Dogs tend to go to the right. A lot tend to stay to the right of what they're searching," Hare explains. "It's something you should know about your dog before you send him to find explosives, if he favors one side over the other. Don't you think that's important information?" him to find explosives, if he favors one side over the other. Don't you think that's important information?"

I'm not sure what the Department of Defense thinks of Hare's ideas, but even if he doesn't get the grant the first time, the DOD should be prepared for more grant proposals in the future. "We want to help save money and dogs and save lives, and we'll keep trying," Hare says.

He and his graduate students are running several studies concurrently. This helps explain the colorful stripes and circles and geometric figures all over the floor of the lab. In certain studies, dogs and people need to be at certain fixed places. Marking up the floor eliminates a variable. The green tape is for the predictions study, the yellow tape is for the inhibitory control study, the worn-out blue tape is for a completed attention study, and the red tape is for the trust study.

The red tape is where we find Alice and Duane Putnam, who have driven for two hours to get here from Warren County, on the border of Virginia and North Carolina. (Staffers here tell me that they get calls from dog lovers all over the world who want to bring their dogs to the lab to be part of the research. The lab tries to limit partic.i.p.ants to no more than a three-hour drive, so the dog won't be dis...o...b..bulated by travel.) The Putnams are here with their dog, Tri, who looks like he's part Rottweiler, part German shepherd, and a bit of something else. They believe he is the reincarnation of two of their previous dogs, thus the name. (Two plus himself equals three. Tri sounds better than Three.) The Putnams are fascinated with their dog. They say he's too smart for his own good. When no one is looking, he opens peanut b.u.t.ter jars and Vaseline jars by s.c.r.e.w.i.n.g off their lids. Then he eats the contents. b.u.t.ter jars and Vaseline jars by s.c.r.e.w.i.n.g off their lids. Then he eats the contents.

Today Tri the Vaseline thief is taking part in the study about trust. He has been here before because his "dog parents," as they call them at the cognition center, like the idea that they're contributing to the better understanding of dogs. Besides, it gets them off their ten acres in the rural corner of the state.

Researcher Jingzhi Tan, aka "Hippo," has devised a study that investigates how trust is established and whether dogs differentiate between owners, a very friendly new acquaintance, and a complete stranger. His goal is actually to find out how humans become friendly and trusting, and he says a good way to study this is through dogs. Many of the studies at the center could end up with significant findings about people as well as dogs.

When I start observing (via a video monitor, so I don't interfere with the goings-on), Tri is being lovingly petted by a new acquaintance-someone who works at the center. She is on the floor with him, making friends like this for about twenty minutes. The Putnams are thrilled Tri is letting a stranger handle him without balking. He's usually not quite as social with people he doesn't know.

Following the petting session, this new friend and a complete stranger will enter the room and take turns sitting next to bowls with food-one bowl will be near the person, one will be near an empty chair. If the dog thinks a person is risky, the idea is that he'd try to avoid that person, and would pick the food that's farther away. Mary, an intern who helps coordinate dog visits here, is the stranger today. But Tri doesn't seem to mind going near her. He is fine with his new friend, too. In other variations of this study, the new friend and stranger take turns pointing to food bowls and researchers see if the dog trusts one more than the other. fine with his new friend, too. In other variations of this study, the new friend and stranger take turns pointing to food bowls and researchers see if the dog trusts one more than the other.

The study, and others like it, could eventually have implications for military dogs and how they come to trust their handlers, but that would be years down the road. What counts now in this room is that Tri, dog number 54 for this study, is done and that he has trusted more people than the Putnams would have thought. They proudly stroke his head and tell him, "You did good!"

Alice Putnam exhorts him: "Kissy Mama!" He doesn't. "He's not much of a kisser," she explains. She says she knows her dog well.

But how well does her dog know her? Chances are, much better than she would suspect.

35

THE SMELL OF FEAR REVISITED

Alexandra Horowitz likens dogs to anthropologists: They study us. They observe us. They smell changes in our very chemistry. They learn to predict us. "They know us in ways our human partners sometimes do not," she says.

I've heard a similar refrain dozens of times from handlers, particularly those who have deployed and spent almost every hour for months with their dogs: Their dogs know them better than their spouses or parents do.

Nearly every handler I interviewed, for instance, said that his dog can tell when he's having a bad day. Most civilian dog lovers would say the same thing. But how can it be that a dog-who doesn't speak your language and doesn't know about problems with your bills or your boss or your in-laws-can somehow sense when things are amiss in your life?

It's a phenomenon many military working dog handlers and instructors refer to as "dumping down the leash." How you're feeling and acting is observed by a dog, who will react to this information in different ways. A tense handler is likely to make a dog more tense. Likewise, if a handler is confident and not fearful, even after a loud explosion nearby, the idea is that a dog who is not already gun-shy will figure there's nothing to worry about, with an instinctual logic along the lines of "My handler's OK with it, and he's the leader here, so it must be OK." tense. Likewise, if a handler is confident and not fearful, even after a loud explosion nearby, the idea is that a dog who is not already gun-shy will figure there's nothing to worry about, with an instinctual logic along the lines of "My handler's OK with it, and he's the leader here, so it must be OK."

Dogs are very sensitive to body language, so the least little tense movement-a change of gait, a slight hunching of shoulders-can be observed and interpreted as something being amiss. When we're upset, our voices can go up slightly in frequency as well. Dogs get these nuances in ways most people don't.

Masking strong feelings by acting like things are OK may not always work, either: It's quite likely that dogs can smell fear, anxiety, even sadness, says Horowitz. The flight-or-fight hormone, adrenaline, is undetectable by our noses, but dogs can apparently smell it. In addition, fear or anxiety is often accompanied by increased heart rate and blood flow, which sends telltale body chemicals more quickly to the skin surface.

It makes for a trifecta of revelations to a dog: a bouquet of visual, auditory, and olfactory cues that makes dogs incredibly tuned in to how we're feeling.

It's comforting to think dogs have empathy and want to see the people they care about feel better when things are not quite right. This sort of action adds to their reputation as man's best friend. But most scientists who study dog behavior say it's more likely that dogs who seem to be acting in comforting, helpful ways simply want to restore order to their pack.

John Bradshaw explained it to me this way: "People are more important to dogs than anything else, and they rely on us to provide them with a stable and predictable social environment. If they sense that anything unusual is going on, that people are behaving in ways they don't usually behave, they will do anything they can to restore the situation. sense that anything unusual is going on, that people are behaving in ways they don't usually behave, they will do anything they can to restore the situation.

"Initially they'll do things that have worked in similar situations in the past. They're not trying to comfort anyone else, they're trying to comfort themselves, but often one leads to the other. The dog picks up a toy and uses it to get someone's attention, usually the person who's behaving oddly (as far as the dog is concerned), but not necessarily. The dog is just craving attention-but if it does this in a "cute" way, then the effect may well be to calm that person down. That is in itself rewarding for the dog, so the next time a similar situation presents itself, the dog wheels out the same strategy. It doesn't know why its behavior has the desired effect, it just knows that it works."

It makes sense. And I've heard this from a few different dog experts. But I prefer my own interpretation of Jake's actions when I'm having a rare bad day. He follows me around significantly more, making an extra effort to visit me at my writing desk. He usually leaves me alone here: This is my turf, distraction-free as possible, which is handy on tight deadlines. But on a tough day, Jake will inevitably scratch on my door for admittance. Happy to see a friendly face, I let him in and pet him for awhile. That alone makes me feel better. Then he usually curls up under my desk, falling asleep at my feet.

It may not be scientific, but it feels pretty good to think Jake has empathy. Sometimes he even seems to pick up on my likes and dislikes, favoring the people I enjoy but getting downright testy with one rude man we see sometimes at the park. Whenever we encounter him, this man snarls at me: "Better clean up after your dog, lady." Apparently he does this to all people with dogs. I don't take it personally, but it's annoying. lady." Apparently he does this to all people with dogs. I don't take it personally, but it's annoying.

The first couple of times this happened, I a.s.sured him of my p.o.o.p-scooping vigilance, but now I just try to avoid him when I see him. But sometimes our paths will cross. When they do, Jake does something he doesn't do with 99.9 percent of the people we meet on our walks. He barks. Just a few good deep bellows, followed by a long stare as if to say, "Leave us alone or else." I don't bother telling him to stop. He'll join up with me within moments, and I quietly cheer him on with a "Good boy!" He may not be wearing one, but my feelings have clearly dumped down the leash.

Of course, Gunny Knight could have told you all about dogs' senses long ago without any studies. "I don't need all that scientific stuff. The best lab is right out here with the dogs, and especially over on deployment. That's where dogs and handlers really get to know each other."

PART FOUR

DOGS AND THEIR SOLDIERS

36