Few animals are as terrifying to humans as sharks. These sharp-toothed, quick-swimming predators haunt the dreams of many a beachgoer (and even those who seldom visit the shore). But statistically, sharks pose very little threat to humans. So why are people so afraid of them?
That's simple. People are terrified of sharks because getting eaten by a shark would be a really "crummy" way to die, said David Ropeik, an instructor of risk communication at Harvard University and author of the book "How Risky Is It, Really? Why Our Fears Don¹t Always Match the Facts" (McGraw-Hill Education, 2010).
"We're not just afraid of things because of the likelihood that they'll happen, but [also] because of the nature of them if they do happen," Ropeik told Live Science. "So it may be unlikely that you'll be attacked by a shark, but it would suck if you did." [8 Weird Things About Sharks]
Just how unlikely is it that you'd get eaten by a shark? Statistically, you have about a 1 in 3,748,067 chance of dying in a shark attack, according to the International Shark Attack File of the University of Florida's Museum of Natural History. To put that into perspective, you're at a much higher risk of dying of heart disease (1 in 5 chance), of cancer (1 in 7 chance) or in a car accident (1 in 84 chance) than you are of being the victim of a shark attack.
And even if you frequent the beach during the summer months, you face a greater risk from other beach dangers than you do from sharks. In general, people have a 1 in 1,134 chanceof drowningand a 1 in 13,729 chance of dying of sun exposure, according to the International Shark Attack File. But these statistics don't seem to matter to people who fear sharks.
Your 'lazy brain'
Fear of sharks is rooted in the brain, and can be understood by examining what Ropeik called "two biological truths" about how the brain processes information. The first of these truths is that humans are hardwired to respond to information with feelings first and thoughts second, Ropeik said. The second truth is that, over time, humans tend to respond more with feelings than they do with thinking.
In other words, when a person "thinks" about sharks, he or she isn't really thinking objectively, Ropeik said. Humans tend to feel scared of sharks first and then, at some later point, consider the actual risk that sharks pose (if the individuals consider this at all).
And this trend doesn't reverse over time. That is, people don't start thinking more rationally about sharks the longer they sit on the beach, pondering the great expanse of water before them. In fact, the longer people think about all the sharks that might be swimming below the surface, the more scared they might feel, said Ropeik, who added that these explanations originated from work done by neuroscientists studying how the brain responds to threats. [What Really Scares People: Top 10 Phobias]
But these ideas leave an important question unanswered: Why sharks? After all, there are plenty of big, predatory animals out there that could kill a person in much the same way a shark can, but you don't often hear people talk about their fear of wolves or bears. This preoccupation with sharks has to do with something that Ropeik calls the "lazy brain."
"We have a bunch of mental shortcuts that allow us to quickly judge situations before we have all the information," Ropeik said. "We make up our mind quickly, because it's easier for the brain to do that. It takes calories to think."
One of the mental shortcuts your brain makes is known as the "availability heuristic" (first described by the psychologist Daniel Kahneman). Essentially, this is the brain's tendency to focus on information that is recent and readily available when making a decision. For example, let's say you watch "Shark Week" programming and read a few news stories about the recent shark attacks off the coast of North Carolina before going on a tropical vacation. While there, you might wade out into the water and feel something rub against your leg.
"When the availability heuristic mental shortcut kicks in, we leap to the conclusion, 'Ah, shark!' without going to the facts," Ropeik said. "We never get to the what-are-the-odds part because the nature of the brain is to take partial information, quickly judge whether there may be danger, and then draw quick, protective or precautionary conclusions before we objectively look at the evidence."
It's particularly easy for people to jump to conclusions about sharks because of the specific kind of risk that sharks pose to humans, said Ropeik. He explained that psychologists have found that there are certain risks that seem more or less scary to a person. A risk that results in a gruesome death (i.e., being eaten alive) is scarier than the risk of a not-so-gruesome death (i.e., falling asleep and never waking up).
The hidden nature of a shark attack also makes it seem more frightening, he said. "It's scary to encounter a risk when you don't know that something is about to happen — like a shark lurking underwater where you can't see it. Uncertainty makes this risk scary," Ropeik said.
The devil you know
If you're not really afraid of sharks, it might be because the risk they pose to you is familiar, Ropeik said. For example, if you live in Florida, where most shark attacks in the United States occur, then you might not be as fearful of these creatures as someone who lives in Maine, where shark attacks are extremely rare. [See Stunning Images of Great White Sharks]
This might seem counterintuitive. After all, wouldn't someone who is more likely to be attacked by a shark be more fearful of these creaturesthan someone who is less likely to be attacked? Not necessarily, said Christopher Bader, a professor of sociology at Chapman University in Orange, California.
Bader and his colleagues study fear — specifically, they investigate what kinds of crimes Americans fear most. The researchers have found that the more familiar a person is with the risk of becoming a victim of a certain crime, the less likely that individual is to fear it. While Bader hasn't specifically studied peoples' attitudes about sharks, he said he thinks the same trend is likely true for shark attacks. In other words, the more familiar you are with your risk of being a victim of a shark attack, the less likely you are to fear such an attack.
But most Americans have a skewed perception of how likely they are to be victims of any kind of crime. And the average American's perception of how likely he or she is to be the victim of a shark attack could be similarly skewed, according to Bader.
"A lot of the work that my colleagues and I have done is about why people tend to have fears about things which are not actually, in all great likelihood, going to be something that they experience. And why their fears are much lower in terms of things that they're more likely to experience," Bader told Live Science.
Last year, Bader and his colleagues conducted an Internet survey in which they asked Americans to divulge how fearful they felt about specific things (the survey didn't include sharks). The results showed that people who reported watching television regularly, including news and crime shows, were more likely than people who didn't watch these programs to think that the rates of certain crimes — such as serial killings, mass shootings and child abductions — had gone up over the past 20 years. In reality, the rates of all these crimes in the United States have declined in the past two decades, Bader said.
"The risk of serial killers and the risk of shark attacks are both extraordinarily low, and these risks have generally gone down over time. But people don't tend to perceive it that way," Bader said.
Like they do with crime, people get most of their information about sharks from the media, which can be a problem, said Bader. He added that when one shark attack occurs, media outlets tend to seize the opportunity to report on other examples of such attacks. This heightened coverage can give people the impression that the rate of shark attacks is on the rise, even though it might not be.
And Bader's research has shown that people who think negative incidents are on the rise are more likely to be afraid that they will be victims of such incidents.
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Elizabeth is a former Live Science associate editor and current director of audience development at the Chamber of Commerce. She graduated with a bachelor of arts degree from George Washington University. Elizabeth has traveled throughout the Americas, studying political systems and indigenous cultures and teaching English to students of all ages.