This story appears in the June 2013 issue of National Geographic magazine.
The man who led a landmark attempt to navigate the entire length of the Grand Canyon did not exactly look the part of a dashing gilded-age adventurer. John Wesley Powell stood only five feet six, had a shock of bristle-brush hair and an unruly tobacco-stained beard that splayed onto his chest. The right sleeve of his jacket hung empty, the result of a minié ball at the Battle of Shiloh. Yet after the war he went on to survey large swaths of the Rocky Mountains, live among hostile bands of Indians, raft the Green and Colorado Rivers, and probe the unmapped labyrinths of one of the world’s largest canyon systems. A stranger might reasonably have wondered what had steered this slight, one-armed university professor to embark on some of the riskiest explorations of his age.
In fact, the same could have been asked of each of the 32 men who joined Powell on January 13, 1888, at Washington, D.C.’s Cosmos Club. Like him, most had pursued their own perilous journeys into unknown wildernesses. Among them were veterans of the Civil War and Indian campaigns, naval officers, mountaineers, meteorologists, engineers, naturalists, cartographers, ethnologists, and a journalist who had crossed Siberia. They were men who had been stranded in the Arctic, survived violent weather at sea, escaped animal attacks and avalanches, endured extreme hunger, and persevered against the soul-crushing loneliness of traveling in remote landscapes.
They had gathered that evening to found the National Geographic Society and had agreed that their new organization’s mission—“the increase and diffusion of geographical knowledge”—would require difficult explorations into unknown territories. Their ethos could be summed up by a passage Powell had written in his journal during his Colorado River expedition almost two decades earlier. After his team, riding in small boats, made several harrowing descents through rapids and over waterfalls, three of the men decided to quit and climb their way out of the canyons, taking their chances crossing the desert. “They entreat us not to go on, and tell us that it is madness to set out in this place,” Powell wrote. And yet “to leave the exploration unfinished, to say that there is a part of the canyon which I cannot explore, having already nearly accomplished it, is more than I am willing to acknowledge, and I determine to go on.”
Exploration of all sorts is rooted in the notion of taking risks. Risk underlies any journey into the unknown, whether it is a ship captain’s voyage into uncharted seas, a scientist’s research on dangerous diseases, or an entrepreneur’s investment in a new venture. But what exactly pushed Christopher Columbus to embark on a voyage across the Atlantic, or Edward Jenner to test his theory for an early smallpox vaccine on a child, or Henry Ford to bet that automobiles could replace horses? For that matter, why did Powell ignore the cautions of his men and the obvious dangers in front of him to venture deeper into the wilds of the Grand Canyon?
Some of the motivations for taking risks are obvious—financial reward, fame, political gain, saving lives. Many people willingly expose themselves to varying degrees of risk in their pursuit of such goals. But as the danger increases, the number of people willing to go forward shrinks, until the only ones who remain are the extreme risk takers, those willing to endanger their reputation, fortune, and life. This is the mystery of risk: What makes some humans willing to jeopardize so much and continue to do so even in the face of dire consequences?
One hundred and twenty-five years after that night at the Cosmos Club, scientists have begun to open up the neurological black box containing the mechanisms for risk taking and tease out the biological factors that may prompt someone to become an explorer. Their research has centered on neurotransmitters, the chemicals that control communication in the brain. One neurotransmitter that is crucial to the risk-taking equation is dopamine, which helps control motor skills but also helps drive us to seek out and learn new things as well as process emotions such as anxiety and fear. People whose brains don’t produce enough dopamine, such as those who are afflicted with Parkinson’s disease, often struggle with apathy and a lack of motivation.
On the opposite end of the spectrum, robust dopamine production holds one of the keys to understanding risk taking, says Larry Zweifel, a neurobiologist at the University of Washington. “When you’re talking about someone who takes risks to accomplish something—climb a mountain, start a company, run for office, become a Navy SEAL—that’s driven by motivation, and motivation is driven by the dopamine system. This is what compels humans to move forward.”
Dopamine helps elicit a sense of satisfaction when we accomplish tasks: the riskier the task, the larger the hit of dopamine. Part of the reason we don’t all climb mountains or run for office is that we don’t all have the same amount of dopamine. Molecules on the surface of nerve cells called autoreceptors control how much dopamine we make and use, essentially controlling our appetite for risk.
In a study conducted at Vanderbilt University, participants underwent scans allowing scientists to observe the autoreceptors in the part of the brain circuitry associated with reward, addiction, and movement. People who had fewer autoreceptors—that is, freer flowing dopamine—were more likely to engage in novelty-seeking behavior, such as exploration. “Think of dopamine like gasoline,” says neuropsychologist David Zald, the study’s lead author. “You combine that with a brain equipped with a lesser ability to put on the brakes than normal, and you get people who push limits.”
This is where the discussion often confuses risk takers with thrill seekers or adrenaline junkies. The hormone adrenaline is also a neurotransmitter, but unlike dopamine, which can push us toward danger in the course of achieving certain goals, adrenaline is designed to help us escape from danger. It works like this: When the brain perceives a threat, it triggers the release of adrenaline into the bloodstream, which in turn stimulates the heart, lungs, muscles, and other parts of the body to help flee or fight in a life-threatening situation. This chemical release generates a feeling of exhilaration that continues after the threat has passed, as the adrenaline clears the system. For some people that adrenaline rush can become a reward the brain seeks. They are prompted to induce it by going to scary movies or engaging in extreme sports or by artificial means such as taking narcotics.
But adrenaline isn’t what motivates explorers to take risks. “An Arctic explorer who’s slogging through ice for a month isn’t motivated by adrenaline coursing through his veins,” says Zald. “It’s the dopamine firing in his brain.”
Critical to this process is how the brain measures risk. Photographer Paul Nicklen describes how his definition of acceptable risks has evolved over time. “When I was a kid living in the Arctic, I would paddle ice floes like rafts, which was probably risky. Then I learned to dive, and I just kept wanting to go deeper, stay in the water longer, get closer to the animals.
“For a long time I told myself I wouldn’t dive with Atlantic walruses,” he says. “The reason there aren’t many photos of Atlantic walruses swimming under polar ice is because it’s incredibly difficult and dangerous to cut a hole in ice that’s several feet thick and dive into water barely above freezing and try to get close to 3,000-pound animals that can be highly aggressive when disturbed. There are a lot of ways to die doing that.”
Nicklen’s reward for taking those risks is capturing walrus images that are so close, so three-dimensional, that they cast a spell over a reader. “I want readers to feel like they are a walrus, swimming with other walruses. For fleeting moments, that’s what I feel like at times. The only way I can describe how powerful a feeling that is is through these pictures. I guess I am sort of addicted to it.”
The movement of Nicklen’s personal “risk line” is his brain’s way of recalibrating risks based on past experience, says Larry Zweifel. “He is very comfortable recognizing what potential threatening situations look like and how to successfully avoid those situations. His brain calculates the risks and the potential reward, facilitated by his dopamine system, which then motivates him to do the dive.”
And yet, says Zweifel, “if he were to repeatedly dive with animals that threaten his life and encounter many near-death experiences but continue to make such dives regardless of the negative outcomes, then that would be compulsive behavior, which can become pathological, like losing everything because of a gambling problem.”
Acclimating to risk is something we all do in our daily lives. A good example of this occurs when learning to drive a car. At first a new driver may fear traveling on freeways, but over time that same driver with more experience will merge casually into speeding traffic with little consideration for the significant potential dangers.
“When activities become routine and familiar, we let our guard down, especially when nothing bad happens for quite some time,” says Daniel Kruger, an evolutionary psychologist at the University of Michigan. “We have a system designed to react to short-term threats, but when it is on all the time, it can have a detrimental impact on the body,” such as elevating blood sugar and suppressing the immune system.
This familiarity principle can also be applied to help deal with the fear associated with high-risk situations. By practicing an activity, humans can become used to the risk and manage the fear that arises in those situations, says Kruger. “Tightrope walkers start by learning to walk on a beam on the ground and then move to a rope just off the ground, until finally they graduate to the high wire. It appears more dangerous to an audience that has never walked a tightrope than it does to the tightrope walker.”
Last October former Austrian paratrooper Felix Baumgartner took this principle to the extreme when he rode a helium balloon into the stratosphere and leaped out, descending 22.6 miles to the Earth. His record-setting parachute jump included a four-and-a-half-minute free fall that exceeded 843 miles per hour.
In preparation for such an epic feat, he and his team had spent five years refining his equipment, using an altitude chamber to simulate the temperatures and pressures he would encounter, and practicing jumps from various altitudes.
“To people on the outside, the jump looks like an extraordinary risk,” Baumgartner says. “But if you look carefully at the details, you find out the risk is minimized as much as possible.”
It is, however, important to remember that a person doesn’t have to jump from space to be a risk taker, says Kruger. “Taking risks is part of our human legacy. We are all motivated to survive and reproduce. To accomplish both involves choices that might lead to negative outcomes. Essentially, that is risk taking.”
The notion that we are all descended from risk takers fascinates writer Paul Salopek. “Humans leaving the Great Rift Valley were the first great explorers,” he reasons. With this in mind, he has embarked on a seven-year, 22,000-mile journey to follow in their footsteps as they radiated out of Africa and across the planet. It is the trail of some of the first risk takers, who along the way took bites of unknown plants and animal flesh, learned to traverse deep water, and discovered ways to sustain their body temperature in cold.
In making this journey Salopek is taking his own set of extraordinary risks. “The idea is to walk the daily length that nomads did when they left Africa 50,000 to 70,000 years ago. Scientists have found that to be about ten miles a day,” he said in January, shortly before he began the trek from the site in northeastern Ethiopia’s Afar region where some of the first anatomically modern human fossils were found. At this pace he plans to pass through three continents and 30-odd international borders, as well as scores of languages and ethnic groups, mountain ranges and rivers, deserts and high plains, dying cities and bustling new metropolises.
Salopek is no novice when it comes to challenging travel. In August 2006 he was covering the conflict in Darfur, Sudan, as part of an assignment for National Geographic when he was kidnapped by militiamen, who beat and threatened to kill him. He was eventually released.
“The philosophy behind this walk is to get readers to focus less on the notion that the world is a dangerous place,” he says. “The world can kill you in a heartbeat, whether you stay at home or leave home.” Instead, he hopes “to get readers to think about the wider horizons, the wider possibilities in life, the trails taken and not taken, and be comfortable with uncertainty.”
Basically Salopek wants to remind people that at our innermost core we are all risk takers, if some more than others. And this shared willingness to explore our planet has bound our species from the very beginning.
It’s a noble idea, albeit one that is fueled by dopamine.