And Then You're Dead Read online

  Sharks like to attack from below and behind, so you would probably be struck in the legs. They also have bad table manners: They don’t chew. They tear and rip by thrashing their heads from side to side and rolling their bodies. From spiral teeth markings on bone we can see that sharks like to saw flesh off and then swallow it whole.

  The good news is that 70 percent of attacks are one bite only. The bad news is that a single bite and rip from a great white shark is more than enough to remove your leg. However, that can actually work for you.

  The great danger in a leg chomping is a cut to your femoral artery. In general, injuries to arteries are more dangerous than those to veins because arteries carry blood from your heart and are under pressure, so when they’re severed they squirt—as opposed to veins, which just drool.

  The femoral is one of the worst arteries to sever. It’s responsible for oxygenating your entire leg, and nearly 5 percent of your blood volume passes through it every minute.

  Exactly how the shark bites your leg would determine whether you have any chance at all. The human body cannot afford to lose 5 percent of its blood volume per minute—that equates to death in four minutes—so you would think that if your femoral artery was severed, your story would be a short one. But that’s not always the case.

  Right now, as you read these words, your femoral artery is under a small bit of tension, like a stretched rubber band. If it were severed cleanly by the shark, it would snap back into the stump of your leg, where your muscles could pinch it shut—slowing the leak and giving you time to get a tourniquet on. But if it were slashed unevenly, or at an angle, it wouldn’t recede correctly—that’s bad. You would black out in thirty seconds. From there you would go into circulatory shock—a deadly positive feedback loop wherein your tissues die from lack of blood, swell up, and compound the problem by blocking blood flow elsewhere in the body.

  Four minutes after the attack, if your femoral was cut unevenly, you would have lost 20 percent of your blood and you would enter a critical stage. Your heart needs a minimum blood pressure to keep beating, and once you lost 20 percent of your blood volume you would drop below that threshold. After that it would only be a few minutes until complete brain death.

  All of this assumes you were lucky and the shark did the expected and attacked from behind. A frontal attack on your head and torso is less likely but worse. Losing your head is bad because, one, your brain is in it and, two, tourniquets are far less effective on your neck than they are on your legs (for details, see Wikipedia for “Hanging”).

  Lawyer’s note: Seriously—do not put a tourniquet around your neck.

  What Would Happen If . . .

  You Slipped on a Banana Peel?

  IF YOU SEE a banana peel on the floor, how concerned should you be? If the cartoons are to be believed, the answer is, of course, very. Cartoons might understate banana peel danger by overstating the strength of your skull, but the cartoons aren’t kidding about the slipperiness of banana peels. Rigorous scientific study has confirmed bananas as the most dangerous of all fruit peels.

  Slipperiness is measured by placing a block of a given material on a ramp of another material and then slowly increasing the angle of the ramp. The tangent of the angle of the ramp when the object starts to slide gives the coefficient of friction (CoF), and it usually scales from 0 (the slipperiest) to 1 (stickiest), though in some stickier situations it can go as high as 4.* Rubber on a cement sidewalk has a near slip-proof CoF of 1.04.

  Then there’s the other end of the spectrum. Sliding on socks across a wooden floor has a CoF of only 0.23, and ice is even slipperier. A walk across an ice rink can have embarrassing consequences because rubber on ice registers a potentially painful CoF of 0.15.*

  Banana peels put all that to shame.

  We know this thanks to a few daring professors at Kitasato University in Minato, Japan, who decided to double-check the cartoons. Dr. Kiyoshi Mabuchi and his team peeled a bunch of bananas, threw them on a wooden floor, and stepped on them with rubber-soled shoes (hopefully they had a spotter). Then they measured the forces involved.

  It turns out Elmer Fudd might not have been as clumsy as we all thought. Banana peels on wood have a CoF of only 0.07—twice as slippery as ice and five times slipperier than wood. Mabuchi and his team of researchers weren’t done, though. Was the banana peel slippery merely because of its water content? Would other fruit peels result in similar slippage?

  To find out they peeled apples and tangerines and ran the same rigorous experiment: They stepped on them. The apple peel came in a distant second, at 0.1, and the tangerine peel was by far the stickiest, with a CoF of 0.225 (about the same as stepping on a wooden floor without a peel).

  So if you’re walking through a fruit factory and have a choice of peels to step on, remember this: It’s not just a joke; banana peels are the worst. Under pressure, a banana peel oozes a gel that turns out to be extremely slippery. Your foot and body weight provide the pressure. The gel provides the humor.

  Why is slipperiness so important? Walking is really just a series of falls and catches. With each step you fall forward, and with the next one you catch yourself and begin the process over again. Banana peels mess up the catching part. If you just stand on a slippery surface, you will probably be okay. But if you take a step, you initiate a fall. To stop it, your leading foot hits the ground with forward momentum at a strike angle of 15 degrees. If you know you’re walking on a slippery substance, you will change your gait to decrease that angle, demand less friction from the floor, and lessen your chances of taking a tumble. Stray banana peels have a way of sneaking up on you, though, and research suggests that taking a normal step on a substance with a CoF of less than 0.1 results in a fall 90 percent of the time.

  Of course, the real danger with falling is injuring your brain, an essential organ that lives high off the ground. Learning to walk upright sometime 4 to 6 million years ago was a big advancement for the human species, but it did introduce the problem of a slip-and-fall. If you were, say, the height of a small dog and you fell, your head would not build up enough speed to do any damage when it hit the sidewalk.* You could dance on banana peels, because the difference between falling twelve inches and hitting your head and falling six feet on the same organ is the difference between a bruise and a broken skull.

  The force generated by an unrestrained falling adult onto something solid is more than enough to crack a skull. In ballpark terms (everyone’s head is a little different) your skull would crack with as little as an unrestrained three-foot fall onto a hard surface. The skull is stronger in the front and back, and weaker on the sides, but even if you fall onto the stronger frontal bone, a fall of six feet is enough to crack it—especially if you pitch forward.

  Either way, if you cannot protect your head from a fall of six feet, your skull would fracture. Fractures are dangerous for a few reasons, but bleeding is the big one. Your brain is a blood hog, which means cracking it results in a lot of bleeding inside, putting you in immediate and deep trouble.

  Bleeding inside your skull can be far more dangerous than bleeding anywhere else. And it’s not just because you can bandage a leg wound and you can’t an internal skull bleed. It’s because your skull is a solid container carrying fragile cargo. If your head starts filling with blood, your brain gets squeezed. Too much blood within your skull creates pressure that strangles the rest of your brain and chokes off and kills critical brain functions, like remembering to breathe.

  Of course your brain knows how fragile it is, and if you slip it works very hard to put something in the way to break your fall—hands, elbows, knees—anything but itself. Which is why you see more bruised butts than broken heads and why banana peels are usually funny, not lethal.

  But “usually” isn’t the same as “always.” And that brings us to Mr. Bobby Leach, the English daredevil of Niagara Falls.

  Since 1901, roughly fifteen p
eople have attempted to go over Niagara Falls for the fame or the thrill (see p. 57 for what happened when they did). Five of them drowned; most never went back. (“I’d rather stand in front of a cannon and be blown to death,” responded the first survivor, “than do that again.”)

  But Bobby Leach was a professional stuntman, daredevil, and circus performer who cheated death for a living. In 1906, he climbed into a steel barrel and went over the falls. He survived, although he needed six months of hospitalization to recover from two wrecked knees and a broken jaw.

  Afterward, he went on to a successful lecturing career, touring the world with his barrel and posing for photos. In 1926, he was in New Zealand when he slipped on an unidentified fruit peel on a sidewalk in Auckland and gashed his leg. A few days later, Bobby Leach died from the complications.

  What Would Happen If . . .

  You Were Buried Alive?

  YOU CAN MEASURE your pulse by putting two fingers on your jugular vein in the crook between your chin and neck. In a minute you should count around seventy beats. If the count is lower than twenty-six, you should finish this chapter in the back of an ambulance.

  If you cannot feel anything, your finger is probably in the wrong place, but even if it isn’t you’re not necessarily dead. Sometimes a pulse is so weak it cannot be felt.* This posed a problem for doctors in the Middle Ages, when feeling for a pulse was the only way to determine if a patient was alive.* Occasionally comatose patients were declared dead, only to wake up in the morgue sometime later. Soon, concerned people asked to be buried with a bell above their grave and a string running into their coffin, just in case.*

  Doctors today have more sophisticated means of deciding whether you’re dead (they look for electrical signals from your heart and brain). But let’s say your physician has an early dinner reservation and cuts a few corners. He signs your death certificate, grabs his coat, and jumps in a cab, headed for dinner and a show. You, meanwhile, are in a gurney being wheeled down to the loading dock and then placed in the back of an ambulance, headed for the morgue and a hole in the ground. What would happen next?

  Once you’re placed in the airtight coffin you would start using up its oxygen. A typical coffin has 900 liters of air and you take up 80 of it, so you would have 820 left. Your lungs take in a half liter per breath, but you use up only 20 percent of the oxygen per breath, meaning you could rebreathe the same air a few times before completely depleting it.

  Of course, you wouldn’t need to breathe every last bit of oxygen before running into trouble. Air is 21 percent oxygen and that’s where you’re happy. Once you began using up oxygen you would quickly run into issues. Breathing air with 12 percent oxygen would give you headaches, dizziness, nausea, and confusion as your brain cells began to starve.

  Your coffin has enough oxygen to last around six hours before you start to asphyxiate—as long as you stay calm. You would think that you would last longer holding your breath, but that actually increases your oxygen usage when your body overcompensates for the CO2 buildup with bigger breaths than it needs. Slow, controlled breathing is the way to go.

  Once the oxygen drops to 10 percent you would go unconscious without warning and quickly fall into a coma.* Sudden death happens at 6 to 8 percent oxygen.

  But here’s where it gets interesting and a little complicated. There’s another issue competing to kill you. By breathing, you are replacing the oxygen in your coffin with CO2.* That’s a problem.

  The excess CO2 you are breathing binds with your blood and limits the amount of oxygen it can carry into your tissues—effectively asphyxiating your vital organs. Air with 0.035 percent CO2 is normal, but in your airtight coffin that percentage rises quickly. Once the CO2 level rises to 20 percent it will render you unconscious in two to three breaths and can kill you within minutes.

  Along the way it will also poison your central nervous system, which would manifest as confusion and delirium—so perhaps you would see a ghost in your coffin?

  Between the increasing CO2 levels and decreasing oxygen, it’s a close race to kill you, but in the end you will be poisoned to death by your own exhales first. The CO2 level will rise to lethal levels in only 150 minutes, killing you two hours before your coffin ran out of oxygen.

  It could be worse, though, if your grave diggers were really in a hurry and skipped the whole coffin part. That might sound like a better alternative—maybe you think you could escape? However, in reality you would die far faster.

  Under six feet of dirt you might as well be encased in cement. Six feet of dirt weighs about five hundred pounds on your chest. In other words: You are not getting out. Regardless of any zombie movie you might have seen, if you ever see an empty grave you can be sure it was an outside job.

  But some good news: You would not immediately suffocate. Most of your muscles are too weak to lift five hundred pounds, but your diaphragm isn’t—which is important. You need it to lift the dirt and allow your lungs to inflate. So you could still physically breathe. Unfortunately, there would not be much to breathe.

  In snow avalanches, which resemble dirt burials, victims who live through the initial slide but are buried under snow have a predictable survival pattern: Every hour the survival rate drops in half, so if you are buried for an hour, your chances are 50 percent; two hours, 25 percent; and so on. Those survival times would probably look even worse in dirt burials, because fresh snow is 90 percent air while dirt is mostly just dirt. Either way, in ice or dirt, forming an air pocket with your arm is key.

  Of course if you’re worried about being buried alive, fear not. You would die long before you made it to the grave. Even if you have a lazy doctor, trips to the morgue are fatal. Before you were buried they would give you the world’s worst blood transfusion. To preserve your tissues, morticians replace your blood with formaldehyde, which is, sadly, or perhaps mercifully, fatal.

  What Would Happen If . . .

  You Were Attacked by a Swarm of Bees?

  MICHAEL SMITH WAS tending to his hive when one particularly adventurous bee flew up his shorts and stung him in the testicle.

  Surprisingly, it did not hurt as much as he had feared—which sparked a question: If that is not the worst place to be stung, what is?

  Shockingly, he discovered that no one had ever volunteered to intentionally sting themselves the hundreds of times necessary to get a firm answer.

  Michael Smith had found a new calling and a new daily routine.

  Five times every morning—always between the hours of nine and ten—he would carefully hold a bee with forceps and press it against his skin until it stung him. The first and last stings were always to his forearm and were used as a control, an automatic 5 on his 1–10 pain scale. The middle three stings were located on whichever unlucky body part he had chosen that morning to test. In all, he tested twenty-five different spots over three months. And to answer your question, this is a man who had already been stung on the testicle, so, yes, he tested that other body part as well.

  It turns out that the least painful places to be stung are the skull, middle toe, and upper arm—they all registered a paltry 2.3 on Smith’s pain scale, followed closely by the buttocks, which scored a slightly higher 3.7.

  At the other end of the spectrum are the face, penis, and inside of the nose.

  Smith discovered that the people who talk about the fine line between pleasure and pain haven’t spent much time with bees on their privates. “There is definitely no crossing of the wires between pleasure and pain down there,” Smith told National Geographic. Although if he were forced to choose, Smith reports he would rather attend his bees without drawers than without a mask. Neither, though, he adds, would make him happy.

  “Stings to the inside of the nostril were especially violent, electric, pulsating,” says Smith, “and immediately induced sneezing, tears, and a copious flow of mucus.”

  The final determination? According to
Smith (and Smith alone, though he welcomes a larger sample size if you’re interested) the penis is a 7.3, the upper lip is an 8.7, and the very worst place to be stung? Inside the nose, an even 9.0.

  Little known fact: One bee sting begets others. When a honeybee stings you it simultaneously releases a pheromone cocktail that lets the hive know it needs defending. The dominant ingredient in this pheromone, incidentally, is something called isoamyl acetate, which is a common ingredient in certain kinds of candy because it tastes like bananas. It’s also used in Hefeweizen beer. In other words, don’t eat banana-flavored Runts or drink a wheat Bavarian beer before rummaging around in beehives.

  If you ignored this advice, you would alarm the hive and peeved bees would fly to the rescue. Stingers are barbed, so when the bees flew away—or tried to—their stingers would stay, disemboweling them and making honeybees natural kamikazes.*

  Even after a stinger is disconnected, though, it works its barb back and forth to dig itself deeper into your nose, all the while pumping its toxin from a sac in the base of the stinger into your flesh.

  A bee sting’s venom works in much the same way that all insect poisons work—by hacking into your cells and changing chemical reactions to produce the results it wants.

  In your case, the bee’s venom penetrates your cell’s membranes using a chemical called melittin. The melittin has a cellular bomb in its backpack in the form of phospholipase A2. If the target is a blood cell it will be destroyed, and if it’s a neuron it will misfire—interpreted by your brain as jolts of pain.

  Still more chemicals go to work on other bodily functions. One restricts blood flow, preventing your body from diluting the toxin, which is why the pain persists, while another builds a sort of chemical bridge within your tissues, allowing the toxins to spread and target new cells.

  You may interpret the experience as a 9 on the bee-sting pain scale, but it’s middle of the road when it comes to insect stings. Which brings us to the other leading authority on the subject, the poet of pain, Justin O. Schmidt.