Sharks, The Navy, & The Availability Heuristic

Sharks, The Navy, And the Availability Heuristic

In the book Grunt, Mary Roach investigates what Navies across the globe do to keep their sailors, pilots, and personnel safe from shark attacks. To some extent, Roach’s findings can be summed up by describing the availability heuristic. Our minds make predictable cognitive errors, and our fear of sharks, and Roach’s subsequent curiosity about how navies protect their personnel from sharks, is in more ways inspired by cognitive error rather than real threat and danger.
In Thinking Fast and Slow Daniel Kahneman writes, “We defined the availability heuristic as the process of judging frequency by the ease with which instances come to mind.” That is to say that we don’t actually have a good mental database of shark attack frequencies relative to other nautical maladies. Neither do we have a great mental database of times when we were successful on the job, the number of electric vehicles on the road, or how many Asian-American actors have been in major motion pictures. We rely on availability. The easier it is for us to think of instances of a shark attack, instances of us doing something good at work, times we saw Teslas in the neighborhood, or whether we just saw Shang-Chi, the more we will think that each of these things occurs with high frequency.
Naval Special Warfare Command communications specialist Joe Kane is quoted as saying the following in Grunt, “You’re coming at this the wrong way. The Question is not do Navy SEALs need shark repellant? The question is, Do sharks need Navy SEAL repellent?”
Shark attacks are sensationalized and make headlines around the world.  Its easy to think of times when we have seen a shark bite victim on the news or when we can remember seeing a news headline about a shark attack. These stories are highly available, so we think they are more common than they really are, and we think they are more dangerous than they really are. After all, a shark encounter that ended with a shark being scared away without trying to bit anyone doesn’t make the news to become available to our minds. Roach writes, “a floating sailor could dispatch a curious shark by hitting it churning the water with his legs. (Baldridge [a researcher Roach spoke with] observed that even a kick to a shark’s nose from the rear leg of a swimming rat was enough to cause a startled response and rapid departure from the vicinity.)”
It is probably still a good idea for naval personnel to think about sharks and how to best train personnel to respond to sharks. However, our fear of sharks is overblown, a consequence of the availability heuristic. Sharks should only be considered to a certain extent, and beyond that, navies will face diminishing marginal returns and unnecessary expenses to try to keep their personnel safe from a minimal threat. It is the availability heuristic they may have to worry about more than sharks.


Across her numerous books, Mary Roach is not afraid to ask the questions most of us probably want to ignore and never think about. For example, in the book Grunt, about soldiers and warfare, Roach asks how the army addresses diarrhea for soldiers in the field. The question is gross and Roach makes it a little funny, but for the army it is not a laughing matter, and it is a serious concern for soldiers.
Speaking with Captain Mark Riddle, Roach learns that soldiers’ gastrointestinal tracts have indeed kept them off certain missions. Riddle explains that one soldier was unfortunate enough to experience diarrhea almost every time he was on a mission, and as a result he was limited to shorter missions closer to army bases. He could not be used for long-term missions that took him deep into enemy territory. You need to be able to process the food and water in underdeveloped or un-sanitized areas if you are going to successfully execute a mission deep into dangerous enemy territory.
At one point, Roach asks a “Special Operations mechanic whether he knows of a vital operation that might have been compromised because someone got a vicious case of food poisoning. He dismisses the very idea. The guys they select for this type of work? They don’t have these types of problems. They’re selected for a reason.”
Roach continues, “20 percent of the population are what Riddle calls nongetters: people who can eat ceviche from street vendors, drink the water, never get sick.” For a whole host of reasons, some probably genetic, some the result of a fortunate set of gut bacteria, and some probably psychological and stress management related, some soldiers simply don’t get sick. During the age of COVID, this is certainly an enviable 20 percent of the population. These nongetters are the ones who are selected for long-term missions deep into enemy territory. They are the ones who can go on foot patrol, mingle with the locals, eat the food they provide, and manage the end results of that food and water. If they constantly got sick, they could not handle the mission, and they wouldn’t find themselves on lengthy deployments. In the army, a strong gut is as important as a strong mind and strong biceps. Nongetters are the ones our army relies upon for crucial missions that put our soldiers’ gastrointestinal tracts in the microbiological firing lines.
Passing Out In The Heat

passing Out In The Heat

I have never over-heated to the point of passing out or having any real problems or long term consequences. I’m lucky that I have not because I do a lot of running and have had a few extremely hot runs in the past. I live in Reno, NV and our high temperatures in the summer can reach into the triple digits and cause problems. When I was in high school the dangers of heat and athletics had become more of a national focus because several high school football players across the country had recently died from heat exhaustion during practices. Possibly one reason why I never had too terrible an experience of running in the heat was because there was an increased focus on keeping high school athletes cool in the during summer practices when I was competing.
In her book Grunt, Mary Roach examines what heat exhaustion means for members of the military. It can be a serious problem for service members in full military gear on patrol in the hot deserts of Iraq or Afghanistan. Luckily, for soldiers and high school athletes, the body has a quick solution, “heat exhaustion is embarrassing but not particularly dangerous. Fainting is both symptom and cure. Once you’re horizontal on the ground, the blood flows back into your head and you come to. Someone brings you water and escorts you to the shade and you’re fine.” Roach continues to explain that heatstroke is what can kill, going a step beyond heat exhaustion.
It is important to be aware of how hot it is, how much water people are able to take in, and how much rest and shade is available as well. It is often not when people are in the middle of exercise that overheating becomes apparent. Roach writes, “counterintuitively, overheated people sometimes pass out not in the midst of their exertions but when they stop and stand still; this is because contracting the leg muscles helps keep blood from pooling.” Breaks and cool down points have to come before people are soo hot that stopping exercise will cause them to faint. Hopefully the fainting an lying flat helps get the blood out of the legs to cool the rest of the body, but if they have gone too far, then they are already in more serious trouble. This was a painful lesson that coaches were learning at the time I was in high school, and hopefully drill-sergeant high school coaches are more aware of the importance of water breaks today.
Injured Veterans, Sex, Divorce, and Suicide

Injured Veterans, Sex, Divorce, and Suicide

I recently published a post about Mary Roach’s book Bonk, where she researched and discussed the researchers and scientists who study sex and sexual physiology. Sex, our sexual desires and urges, and how sex fits into our lives is generally understudied and taboo. This may not seem like a big problem on the surface, but a lack of understanding of human sexual relationships can contribute to divorce, depression, and even suicide.
Roach returns to the idea of our sexual taboo in her book Grunt, specifically asking what happens to wounded soldiers when they get back from war and still have sexual desires, but may be challenged sexually as a result of their injuries? How does an amputee still have a pleasurable sexual relationship with their wife? How does someone with genital injuries engage in sex? Does anyone help these individuals, and what happens to them when they can’t get help or speak with anyone?
In the book, Roach roach asks about the divorce rate for injured veterans. She quotes Christine DesLauriers who founded the Walter Reed Sexual Health and Intimacy Workgroup as saying, “Divorce rate? How about suicide rate. And what a shame to lose them after they’ve made it back. We keep them alive, but we don’t teach them how to live.” This quote shows the seriousness of our society’s sexual taboo when it comes to injured veterans. It is likely that many of the men who go into service fall into the typical macho-man stereotype (though certainly not all!) and it isn’t hard to imagine that many of these men want to have plenty of sex, as would be typical within the stereotype. Failing to help them adapt to injuries, losses of limbs, or reconstructed penises means that we fail to help them adapt to a new life. As DesLauriers was quoted saying, we fail to help them live, and that can lead to depression and a feeling of disappointment that may lead to suicide.
Hopefully our sex taboo doesn’t push most of us to suicide or depression, but it certainly makes it harder for us to have conversations with our sexual partners about what we want in a physical relationship. Without being able to discuss research on sex, we don’t know what is normal, what is abnormal, and how we should handle sexual feelings and urges. At the extreme, this may leave wounded soldiers feeling like they can’t live up to expectations of what it means to be a man, but for many, it may create confusion and dissatisfaction with a sexual lifestyle or a partner. Bonk and Grunt both make a case for being less ashamed to talk about sex, especially within academic, scientific, and medical contexts, so that we can live better lives and better adapt to our sexuality and changes in our physiology throughout our lives.
The Military has a Quiet Problem

The Military Has a Quiet Problem

My wife and I have had a difficult time training our dog not to bark at people across our fence. We have an e-collar that provides muscle tension (not electric shocks) to help correct our dog’s behavior, but we don’t normally keep it on our dog. We were taught to use it as a corrective aid, putting it on the dog in specific situations and using it to correct specific behaviors. The prongs push into the dog’s neck and if they get wet can cause sores on the dog’s skin, so its best not to keep it on her for long periods of time. It also isn’t helpful if it is always on her and activated in situations where it isn’t very clear what behavior we want to prevent. Since it is somewhat rare that our dog barks at people across the fence (she is fine with about 80-90% of people and dogs that walk by) it is hard to pinpoint the specific times when we want to use the collar to try to correct her behavior.
Our challenge with the e-collar and correcting our dog’s behavior is pretty similar to the problem the military has with promoting the use of hearing protection among soldiers. The military wants to protect its soldiers’ hearing and has spent money equipping soldiers with ear plugs, ear muffs, and other hearing protection, but it is hard to actually get soldiers to use the tools provided to them. A major problem is that the hearing protection limits hearing to a point where soldiers would be disqualified from service if their hearing had naturally diminished to such an extent. In modern war, where most of the time there isn’t actual fighting and explosives, this is a barrier to the use of hearing protection. Mary Roach writes about this in her book Grunt:
“There’s no linear battlefield any more. The front line is everywhere. IEDs go off and things go kinetic with no warning. To protect your hearing using earplugs, you’d have to leave them in for the entire thirteen-hour patrols where, 95 percent of the time, nothing loud is happening. No one does that. That’s why [audiologist Eric] Fallon says the Military doesn’t have a noise problem. It has a quiet problem.”
Most of the time soldiers are not being shot at and IEDs are not exploding around them. But occasionally, those things do happen. Soldiers have to talk to local citizens when the shooting isn’t happening. They need to hear if someone is walking up behind them. They need to communicate in a normal manner among themselves. Ear plugs mean they can’t communicate without shouting, and that they can’t hear if someone is sneaking up on them or trying to be stealthy around the next corner. Most of war is relatively quiet and boring, so ear protection is not used.
With the unpredictable chaos of actual conflict when a firefight breaks out, the use of ear plugs is further confounded. Soldiers may not be in a position to prepare and put on ear protection at the outset of a fight, and they likely can’t pause to get their ear plugs or ear muffs on once things go kinetic. They can’t predict when or where an IED will go off and need to hear what direction fighting or shouting is coming from to best protect themselves. All of this complicates the development of new forms of hearing protection and prevents the uptake and use of existing hearing protection. The quiet problem is what leads to the noise problem and the hearing loss of soldiers. If they knew when it would get loud, where it would get loud, and could put themselves in place with hearing protection at the start of a fight, then ear plugs would work well, but the reality is that things are not so linear, and most of the time things are quite, so ear plugs cannot be used.
Hearing Loss in War

Hearing Loss In War

Hearing loss for soldiers is a major problem for individual soldiers, the armies relying on soldiers, and the societies that soldiers return to after a war. First, soldiers have to be able to hear on a battle field. They need to communicate with each other and hear threats coming. But after the war, soldiers need to be able to hear to reintegrate into society. Hearing makes a big difference with finding a good job and getting back into daily life. Finally, hearing loss has a social cost as societies try to cover the healthcare needs of soldiers who return from serving their country.
When soldiers are on the battle field, their hearing is both crucial and under threat. We hold guns in a way that brings them close to our head so that we can aim and sight the weapon while shooting. This means that our ears are next to the loud bangs of the gun as we fire it. Beyond shooting a gun, soldier’s hearing is still threatened by heavy machinery, jets and tanks, large artillery weapons, and other explosions. There is no shortage of bangs, booms, and shrieks that could harm a soldier’s hearing.
Many of these noises are not important and can be blocked out to help protect a soldier’s hearing. Ear plugs to cut the sound of a gun being fired by our head, to block the screams of overhead jets, or to muffle the explosions of bombs can be great. But those same ear plugs can make it hard to hear the footsteps or whispers of an enemy combatant. They can make it hard to hear battle commands or the small sounds that help a soldier orient themselves in a territory where hostile forces could be hiding among civilians or natural terrain. Mary Roach quotes a military official in her book Grunt to describe the challenges with using ear plugs for hearing protection:
What are we doing when we give them a pair of foam earplugs? says Eric Fallon, who runs a training simulation for military audiologists a few times a year at Camp Pendleton. We’re degrading their hearing to the point where, if this were a natural hearing loss, we’d be questioning whether they’re still deployable. If that’s not insanity, I don’t know what is.
Earplugs and earmuffs are used to block out sound to protect hearing because we need our soldiers to have good hearing. But at the same time, they make it so that our soldiers can’t hear the things they need to hear. They diminish how much someone can hear to a level that would disqualify them from service. One result is that soldiers don’t always wear the ear protection they are provided and end up with substantial hearing loss. In both situations, whether they wear ear protection or not, there are serious costs to the soldiers on the battle field, and that can be the difference between life and death for that soldier and the soldiers depending on them.
When soldiers have hearing loss and return back to society the costs continue. Hearing aids are expensive and not always comfortable or super effective. In the Untied States we make a big effort to pick up the tab of medical expenses for our soldiers (even if we don’t always do a great job covering all the costs and providing the healthcare that veterans need). This means we continue to pay for battlefield hearing loss long after a battle has ended. And if we can’t get the hearing right, then the veteran may have trouble working, trouble reconnecting with family and friends, and trouble living a stable life. These individual costs add up and become societal costs if the soldier receives disability pay or becomes homeless. Pretty much everyone agrees we should take care of our veterans and their health, since they put their lives and bodies in the line of fire on behalf of our country, and this means that the costs of hearing loss come back home with the soldier. Hearing loss is a major problem for the army and nation whether in combat or back in civilian life.
Unorthodox Thinking & Large Budgets

Unorthodox Thinking & Large Budgets

“Surprising, occasionally game-changing things happen when flights of unorthodox thinking collide with large, abiding research budgets,” writes Mary Roach in her book Grunt: The Curious Science of Humans at War. Militaries face far more than just opposing combatants in war. Their needs go far beyond bombs, tanks, and fighter planes. Armies need lots of things for basic survival, and sometimes this means that large research budgets are devoted to small topics where institutionalized dogma has not set in. The results can be weird, sometimes less than what the army hoped for, and – as Roach notes in the quote above – sometimes game changing.
In Grunt, Roach highlights some of the examples of incredible, yet unexpected scientific breakthroughs that have come from military research. Medical trauma research, clothing research, and other less thought of research has been crucial for saving lives during war. These are not the first things we usually think about with armed conflict, but without winning in these small areas, armies may not be able to win on larger geopolitical stages.
Entire industries and societies may deal with problems for years without the huge funding and sometimes unorthodox thinking that an army can bring to a problem. Something small, like sweaty and sticky shirts, may plague people for years and be a minor annoyance, but for an army, where keeping moral and camaraderie up is a key for success, a sweaty and sticky shirt could end up being a life or death matter. Bringing in a scientific research team, that doesn’t have the same constraints as public researchers at a university or researchers for a for-profit corporation can open up new avenues of discovery. A researcher at a public university may be shunned away from research on sweaty, sticky shirts because they don’t want their colleagues to think they are working on a goofy topic. Private companies may not see enough of a profit motive in researching sweaty, sticky clothes and may not hire anyone in their R&D section to focus on the issue. But the army can provide some level of intellectual freedom in asking researchers to tackle strange areas and can bring the necessary funding to find a breakthrough. This idea is at the heart of the research that Roach presents in the book.
The sometimes game-changing breakthroughs are not the result purely of lots of money or purely unorthodox thinking. The breakthroughs are the result of a web of factors that include the money, the intellectual space for unorthodox thinking, and the willingness to allow people to focus on sometimes narrow or obscure topics. It also requires obsessives who are not afraid to spend years researching something strange or off-putting. the kinds of breakthroughs people make often don’t get much attention, even if they are very important and make it into daily life beyond the initial military use, but over time they pile up to become part of our way of life. Perhaps we would have gotten there independently of the military, but sometimes that extra funding and unorthodox thinking is needed to help push new innovations and discoveries.