‘He Couldn’t Believe I Flew All the Way to Djibouti to Talk About Diarrhea’: An Interview With Mary Roach

In her new book, Grunt, Roach points her flashlight to the lengths we’ll go—and have yet to go—to keep people alive.

Matthew Braga is a National Magazine Award-nominated freelance journalist covering science,...

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Under the hot morning sun of an otherwise perfect summer day, I watched a girl bleed out by the side of a pool. The water was calm, in spite of the heat, and in stark contrast to the look of distress on the girl’s face. She pleaded for help as I worked, my hands shakily taping the corners of a plastic triangle, snipped hastily from a grocery bag, just beneath her left breast while someone called 911.

I knew I was supposed to be scared—of the wound, of mistakes, and of death. But fear is hard to muster when no-name ketchup is smeared across your arm, a crude simulacrum for the spurting of blood that might complicate your treatment of a sucking chest wound. Rather, the ketchup was a reminder that this was merely a simulation—that there was no wound, no blood, and thus, nothing to fear. What I really felt was nervous, an awkward teenage boy giving first aid to a bikini-clad girl while a group of fellow lifeguards-in-training looked on.

Every few months there were sessions like these, which turned the treatment of spinal injuries and heat exhaustion into a macabre game of charades. We cycled through scenarios and used each other as victims, competing to be a strange kind of best—the most limp, the most still, the most effective at sinking to the bottom of the pool. We were all outrageously, comically bad at acting injured, which was part of what made it so fun.

At Strategic Operations, a provider of hyper-realistic combat simulations for military personnel, this sort of amateur teenage role-play doesn’t cut it. The company has a mock Afghan village in San Diego. Volunteer victims, who are actual Marines, don $57,000 wearable carnage simulators that spurt blood and bodily fluids when cut. “Wound artists” use photos of actual injuries to sculpt protruding bone and mangled flesh on the stumps of actual amputees. Explosions and gunfire echo from loudspeakers overhead, adding another flourish of authenticity for medics-in-training at the company’s combat trauma management course. Unlike my ketchup-slicked arm, the professionals use special effects blood.

“They aim to subject the trainees to as much fear and stress as they can,” author Mary Roach writes in her latest book Grunt: The Curious Science of Humans at War. If the scenario feels real enough, combat medics in training will hopefully be better prepared for the real thing, and come away with a sort of emotional inoculation. Authenticity, in this case, can make the difference between life and death. For all the stories that have been written about conflict and war, this is not a narrative you often hear—that panic, stress, fatigue, and fear can be as deadly to those in the field as someone holding a gun.

There’s more work being done in this area than you might think. Typical crash test dummies are only designed to measure impacts from the front, back, and side, so the US military has been using cadavers rigged with sensors to more accurately gauge the impact of an IED blast from below. Roach visits a Jacuzzi-sized pool, forty feet deep, that students at the Naval Submarine school use for submarine escape training. She dons a special headset that simulates what it’s like to be in a combat situation with hearing loss (it probably won’t come as a surprise that your proficiency with a weapon plummets when you can’t accurately hear who’s shooting—or shouting—at you, and from where). And because carrying a backpack full of equipment in the Afghanistan heat is no walk in the park, researchers have designed a “cook box”—a treadmill in a heated room—to more accurately gauge the body’s heat tolerance over time.

“I’m not covering weapons technology or torture techniques,” Roach told me via phone from Oakland on a recent afternoon. “It’s things that are making soldiers, for the most part … safer, or helping put them back together.” The closer we can get to understanding—and simulating—what can happen to bodies during war beyond the obvious threats and stressors, the more effectively we can help soldiers survive.

Looking beyond the obvious is typical of Roach’s books. In Bonk, Roach’s dive into the science of sex, the act itself takes a backseat to the oddball characters and curious contraptions involved in its study. In Packing for Mars, she tackles the logistics of long-distance space travel as if it were a routine trip to the beach. “I am not, by trade or character, a spotlight operator,” she writes in the introduction to Grunt. “I’m the goober with the flashlight, stumbling into corners and crannies, not looking for anything specific but knowing when I’ve found it.”

Obviously, as a teen lifeguard, the stakes were never as high as they were for those preparing for war. We would ask our instructors—veteran lifeguards themselves—if they had ever done CPR, or if they had ever had someone die. The answer was always no. The likelihood we would ever have to use these skills was, statistically speaking, always quite small. Contrast that with Roach’s time at the Strategic Operations boot camp, where the level of authenticity was in a whole other league—”a vest-like rib cage with an insert tray of abdominal organs and, over this, a kind of flesh-tone wetsuit-simulated skin that bleeds when pierced.” With the spectre of death ever present, Roach points her flashlight just off to the side, to the lengths we’ll go—and have yet to go—to keep people alive.

Matthew Braga: The military seems like the last place that would be willing to open its doors to a curious reporter. How did you manage to convince everyone from a US submarine commander to a far-flung command base in Djibouti to let you spend multiple days working and interviewing people in those sorts of places?

Mary Roach: I am very, very persistent. The Triton submarine, that took over a year. It wasn’t because people were saying no. In that case, it was because subs are out for a long time. They’re out for months, and I’m only looking to be aboard for a few days. So first of all, waiting for an opportunity like that. But the other thing that happened is that, I was lucky. I was talking to the director of research at [the] Naval Submarine Medical Research Laboratory, who happened to be a reader of my books, and he said he was retiring the next year. He said, “We in the navy tend to be kind of closed and I don’t see why, because we do good work and we should share it.” And he’s like, “I’m retiring, I don’t care what they say. I’m going to make this happen.” So he and a number of other people there were incredibly supportive and they just kept trying different avenues. And I would just, every three weeks, send another email or call. “Hey Jerry, it’s me again!” There were probably thirty emails saying, “Hi, it’s me, just checking in again, any progress? Any news?”

It was never a case of just putting up barriers and being squirrelly. Which, I guess, going into the project, I thought I would get some of that, but I never really did. If something was classified, the answer was right up front, “No, this is classified” [or] “no, you can’t.”

I won’t say it wasn’t difficult. It was time consuming, but not frustrating, because people were pretty straightforward. It was much easier than dealing with corporate public affairs offices or even sometimes university public affairs, which I did not expect.

For all the cool stuff that you got to see and talk about, such as the cadavers wired up as zombies, did you ever get the sense that maybe the really really good stuff was behind the curtain or classified or top secret?

No, I didn’t. I’m not covering weapons technology or torture techniques, it’s all good work in terms of, it’s things that are making soldiers, for the most part, safer, or helping put them back together. So there’s not really a lot to hide in the stuff I was looking into.

I imagine if I were trying to write a book about the intelligence arm of the military, or weaponry, or explosives, that could be a whole different situation. First of all, a lot of it would be classified, but second of all, it’s not a story they might be as eager to tell.

Right, and I guess there’s not as much of a worry that if they start to talk about their fancy new canvas, where oil beads and it falls right off, that’s not going to shift the tide of some foreign conflict.

No, no, not at all. Some people are a little paranoid about it, like, “Oh, am I going to get in trouble? Am I allowed to talk about this or not?” regardless of how benign the topic is. So there was a little bit of that, but not from most people.

Did you have to get any sort of clearance to enter a lot of the labs or spaces you spent time in?

No, I have no clearance and I didn’t need any for the places that I was. When I was on the Triton sub, there were whole portions of the sub [I didn’t have access to]. Like, I couldn’t go into the reactor room. There were certain areas, because of the technology or what was going to be on the screen or whatever, certain areas that I wasn’t allowed to go. But they weren’t areas I was really reporting on anyway. The only place that I had wanted to go but couldn’t go was the camouflage laboratory, oddly enough.

Was there anything else you had on your wish list going into this process, that you had either researched or come across, that the military was like, “absolutely not”?

I wasn’t able to embed. Not because of anything specific that I wanted to do, but because it was during the drawdown in Afghanistan, and they were only supporting daily journalist embeds. That was unfortunate, because there were a number of things that I would have liked to cover: medevacs, the army blood system. But the other side to that is, because it was during the drawdown there, happily, weren’t a lot of US personnel being medevac’d. So that didn’t happen. The camouflage chapter, I wanted to have a chapter called “How Not To Be Seen,” and that had to be skipped.

My editor was keen for me to go out with the Navy Seals on a mission. [I was] like, “No, that’s not going to happen. Classified.” But I tried! I called up the public affairs office of the special operations command, and tried to pitch them. I thought, maybe if I covered the weather guy— because sometimes there’d be a weather person on a mission, and I thought that was interesting, because it can make or break a mission, but it doesn’t have the same cachet to be the weather guy. And I promised the public affairs guy, I was like, “I will only talk about weather. I won’t discuss anything else.” And he was like “No, it’s not gonna happen.”

I think that’s one of my favourite things about your books, and this book in particular. You have a knack for finding these weird jobs and departments that you just never would have imagined existed. Like the Navy Entomologist Center of Excellence. Was that a surprise, that you kept coming across these things that were too wacky to believe?

Oh yeah! Yeah. Because I’ve never spent any time writing about anything within the purview of the military, and it was all new to me. The fact that there’s a [Naval] Submarine Medical Research Laboratory, and that there’s a guy working on a diarrhea clinical trial for the navy, that military entomology is a branch of science—I had no idea.

Initially, one of the things I came across earlier that just floored me was the fifth or fourth Marine Corps Dental Battalion. The Marine Corps has a Dental Battalion! I had no idea. So for much of the book, yes, I was surprised and delighted in many cases that these things existed, because that’s right up my alley.

In the chapter on uniforms and accessories that soldiers carry, I came across a Hook and Loop Task Group, which is part of the clothing subcommittee. And there’s an entire task group for Velcro. That was kind of spectacular.

And that the US government’s specifications on buttons runs thirty-plus pages or something. I had no idea that there was this whole publicly accessible library of government specifications for arcane or obscure items. And maybe this only appeals to people like you and me, but is it as fun to browse through as it sounds? Because I read that and thought, “I’d love to kick back on a Friday night with a beer or a glass of wine and see what I can find.”

We may be weird. It’s possible we are very weird. Same here. When I got the folder for the Who Me?, that stink paste in World War II, the [Office of Strategic Services] declassified file, I remember sitting down—my husband was gone, it was just me—and thinking “This is my kind of Friday night.” And just reading these correspondence, I mean, it doesn’t get better than that for me. I can’t tell you how much time I wasted looking at government specifications for seemingly obscure things. Like, yeah, a button. A button!

On the flipside, since you’re dealing with military related stuff, was the process of sourcing information or military research more difficult and different than your previous books? Is that research just floating around publicly or did you have to ask them for access?

There’s the Defense Technical Information Center (DTIC), which is, I think, a searchable website, and a lot of stuff is on there. But I have a sense that a lot of stuff also is not on there. [And] it’s drier than I wanted it to be. I would put in fun keywords that you can put into Pub Med or [the NASA Technical Reports Server], and your search would be a little more fruitful than it was on DTIC. I don’t know, there’s a barrenness on that particular site—it’s massive, and you just think there should be more fun stuff. I put in all kinds of keywords to find interesting, esoteric, approachable material, and I found very little, considering how much time I spent on there. Probably hundreds of searches I did over the two years. So it wasn’t the same wealth as, say, for Bonk—sexual physiology papers, there’s just a tremendous wealth of fabulous material to play with. This one less so. I think there are fewer footnotes in this book, definitely than in Bonk, and even Packing for Mars.

I think you’ve described this a bit in past interviews, but why the footnotes? And why so many footnotes? What is the function they serve? I love them, and they’re always so funny and—

And that is why. That is why. It’s stuff that I couldn’t fit into the narrative. It would be too much of a side trip. It would be too much of a distraction to put it in parentheses. But I can’t bear to leave it out. So it’s relevant, but it doesn’t fit anywhere, so I’m like “Screw it, I’ll put it in a footnote.” So it’s just me, indulging myself, and not leaving out something that I can’t bear to leave out. Like that paper on the hazards of beards among laboratory workers who are dealing with biological weapon-type pathogens. They had this head that you can put this beard onto with real hair, and then they expose these chicks [to pathogen-laced beards], and they would see if the chicks would contract the illness. And that’s horrible for the chicks. But anyway, that paper, it didn’t quite fit with any of the discussion in the chapter, but I wanted to put it in anyway. That one cried out for a footnote.

You have this knack for finding really good characters, and I wonder, are you just really lucky in finding compelling people that leap off the page in every chapter? Or are you going through tens of interviews for each of these chapters with characters that don’t make the cut before you find one that’s worthy of being the star?

I think it’s a combination. I think I am a little bit lucky, but you know what it is? Most people who are passionate about something that seems a little bit obscure are really interesting. Like George Peck, the maggot-fly entomologist. I just think, probably, anybody who has a job that centers on flies and maggots is bound to be pretty interesting [laughs]. He was especially interesting.

I can think of two people who ended up on the cutting room floor. And they were perfectly interesting. It’s just that there was a better scene that came along. It wasn’t that they weren’t interesting. Most people are pretty interesting. It’s rare that somebody would would turn out not to be interesting enough. Because usually it’s their work that gets me to them, and I know that the work sounds interesting, so they’ve been pre-screened in a way. Because it’s like, that’s the guy who did this paper, and that’s a really interesting paper, so it kind of weeds them out that way.

Does part of it fall upon you and your ability as a good writer to find the aspect or topic that’s going to bring them out the most, to make them the most animated?

Oh for sure. I have zero tolerance for PowerPoints. Like, if somebody says to me when I get there, ‘Oh, I’d just like to show you my PowerPoint,’ I’m like, ‘No, shut the laptop, shut it down. We will not be watching your PowerPoint. Sorry. Nope. Nope! No, no no.’ ‘Oh I just thought it’d be a good overview—’ No! Nope. I’m ruthless. I’m keeping people away from giving me what they think that I want, because I don’t want that. I don’t necessarily know what I want, but I don’t want that.

And I also stick around for a couple of days, so the longer you are there, the more material that will come to the surface, and the conversation will wander off to different areas. Because I don’t know, when I get there, what the questions are to ask that will take me to the most interesting things. They have to show me what the questions are. And it’s partly just taking the time to let things unfold.

It’s also steering people away from something that you know is too dialled down and specific. A lot of times, the work that they’re doing at the time that I visit is just too specific, I’m looking for a much more general treatment, so I have to be really straightforward and say, ‘I know this seems really basic to you, and really simplistic, but this is what I need from you. Can we just talk in a general way?’ I’m very much like a sheepdog, keeping them on track towards what I know I need to get. And sometimes it’s a visual thing. I know I need a scene, I need something happening, something that I can write about and describe. It isn’t necessarily the specifics of the science, because I can always call back. I need something to happen that will make an interesting scene.

I was going to ask: What makes a perfect scene, or the best scene possible for you? Because I think great scenes are part and parcel with the Mary Roach book experience.

I guess I know it when I’m in it. Like when I had to walk across the dining facility and approach that very scary special operations guy to talk about diarrhea, it was one of the most awkward things I’ve had to do as a reporter. Partly because of who he was, partly because of the topic. The combination of him and me, and also Seamus, the public affairs guy [in Djibouti], who was adorable and hilarious. I knew that that was going to be a really fun scene.

When they’re happening, you know it. I knew I had to have that scene. So I was like, ‘Seamus can you send out an email to the base? Seamus, can we go and talk to these guys?’

I know what I want. I need to have that awkward conversation with a special operations guy about diarrhea, but I don’t know how to make it happen. So it’s a lot of just trying every possible way to get it to happen. I don’t know exactly what it’ll be, but I have to keep pushing.

The special operations guy, Carey, why were you trying to approach him? And what was it about this particular character—what did you want from him and why did you want to talk to him?

Because special operations units like Navy Seals Teams and things, they’re the ones that get diarrhea, and it’s a rate twice as high as anyone else. And the rates are pretty high with everybody that’s serving in Afghanistan or Iraq, because they’re not hanging out in the base where the food is safe and the water is safe. They’re out in villages, and they’re eating food that might not have been refrigerated, and water that’s not safe, and they get really bad food poisoning. And they’re also doing really high risk, high security, small-classified missions. So it’s like, diarrhea is something that we all giggle about, but it can actually be a threat to national security. So I wanted to have that conversation with somebody. “Have you ever been on some sort of mission to go, I don’t know, take out some Al Qaeda operative, or clear a compound, or whatever it is you’re doing as a Navy Seal, have you ever had a situation where you need to shit your pants?” You can’t step away from a mission. There’s only three guys, and once it’s underway, it’s underway.

And these guys, they’re not chit-chatty fellows. They don’t interact with the other people on the base. They keep to themselves, they’re not approachable, and so, it was like I was stalking this guy. And it was just one guy I chose. He was like central casting, special operation. You can tell because they have beards and nobody else does.

And that was why, because that was the conversation I need to have. It wasn’t enough to just have the researcher say, “Yeah, the rates of diarrhea are twice as high in special operation.” I wanted to then have the conversation and [have him] tell me an actual story.

One of the things I like most in that conversation is that it seemed like you were pulling teeth trying to get that information you were looking for. You mentioned earlier that scientists tended to be relatively open, but was the response you got from people like Carey, did that tend to be harder? A lot of poking, prodding—was that the case with a lot of the military people?

No. In his case, it’s because the mission was classified and he couldn’t reveal much. And also, he couldn’t believe that I flew all the way to Djibouti to talk about diarrhea. He’s like, ‘What the fuck? Who would do that?’ He kept saying, ‘What is the mission here? What is the goal? Are you from WHO? Who are you?’ He just didn’t really buy my story, which if you do what he does, you don’t take people at face value. You always assume someone’s lying. I guess that’s part of being special operations. Because he was worried. He wasn’t uncomfortable talking about diarrhea. It was just like, ‘What are we really doing here? Why do you want to know this? Who are you, really?’

But in general, to answer your question, on the submarine I got a certain amount of yes ma’am, no ma’am, because if you’re just a basic sort of rank and file submariner, you don’t want to get in trouble.

With this book in particular, you primarily focused on the American military. Was that an intentional decision, or was there just lots of fascinating stuff with other militaries that ended up on the cutting room floor?

It was not intentional. I had initially hoped to cover some stuff on the Indian military. I had hoped to cover maybe the Israeli army, the Brits. But it just took so long to get up to speed with the US—getting permission, getting my ducks in a row for things. Each chapter in the US took enough time that [with other militaries] I would have had to start from scratch.

I emailed, called and faxed numerous people in India and just got nowhere. They just don’t reply to email. They just don’t reply. When I’d call it was, ‘Oh, he’s out of town.’ ‘Oh, he’s not here.’ So I just kind of gave up. I spent a lot of time calling and emailing people in various labs there and got nowhere. I did report one thing that didn’t have to do with this book. It was very difficult to get access to. It was nothing—a pepper spray made with the world’s hottest chili pepper. It was nothing. There was no reason why they shouldn’t talk about it. But it was such a big deal, and they weren’t giving me permission, right up until the day I arrived, so it was a lot of banging my head against the wall. And I sent a few emails to the Israel Defense [Forces], and didn’t get a reply. The US logistics of setting stuff up was taking enough time that I didn’t push it.

I know earlier I asked you about a wish list of things you wanted to include in the book but couldn’t. But what about things that you were able to report or research, that you saw or visited, that didn’t make the book?

I was going to have a chapter on blood—historical, and also the current army blood system—but there wasn’t much going on with blood supply, and I couldn’t be there. I couldn’t report on the field, which is what I wanted to do. So usually, it was an access issue. The only scene that didn’t make it in was from the hearing loss chapter. There was a project with the Marine Corps paintball team wearing hearing loss simulators. The researchers were looking at how hearing loss affects survivability and lethality. So that was kind of interesting. Then I, after the fact, found out about the audiologists running around with the Special Operations Marine Corps people, and that seemed a little more dynamic and entertaining than the paintball. I didn’t feel like the chapter could hold both of them.

How do you cope with scientific progress and research continuing apace as you work on a book like this?

I do that by not being very focused on new technology. I’m not a tech writer. Other than that PCAPS [hearing loss simulator] system, there’s not a lot of technology in the book. It’s really, ‘How does sweat and heat-stroke work?’ and ‘What about sleep and circadian rhythm?’ It’s really general, and generally how these systems work, and what the challenges are. So a lot of it, the challenges don’t change, it’s just the approach that changes. So there may be new developments that come down the pipe as the years go by, but the basic science and the challenges are pretty stable.


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