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Because nature is so soothing, right? So relaxing? No—because it’s Red Bull for the brain.

Or so University of Michigan researchers found when they ran a series of tests in 2008 pitting, essentially, Your Brain In The Woods vs. Your Brain On Asphalt. Student volunteers were given a series of numbers and asked to recite them in reverse order. Then they were split up and sent on a roughly one-hour walk: half of the volunteers strolled Huron Street, in downtown Ann Arbor, while the other half meandered the Arboretum. When they got back to the lab, they were tested again. This time, Arboretum crew didn’t just outscore the street walkers; they outscored themselves. “Performance on backwards digit-span significantly improved when participants walked in nature, but not when they walked downtown,” the researchers found. “In addition, these results were not driven by changes in mood, nor were they affected by different weather conditions.”

But maybe it was a matter of noise? Maybe the city walkers were temporarily frazzled from all that traffic clatter. So the researchers came up with a new experiment, and that’s when things got really interesting. Volunteers were given the same test, but instead of going for a walk afterward, they were shown pictures of either urban or woodland scenes. Then they were retested. Once again, City lost to Nature—and not just to nature but fake nature. So if you think sunsets and seacoasts are just pretty views, the researchers concluded, you’re making a big mistake. “Simple and brief interactions with nature can produce marked increases in cognitive control,” they explain in a paper for Psychological Science called “The Cognitive Benefits of Interacting with Nature.” Treating that oceanfront hotel room “as merely an amenity,” they add, “fails to recognize the vital importance of nature in effective cognitive functioning.”

That’s all it takes, just a reminder of our ancestral past can be enough to flip a switch in the brain that focuses attention and shuts out distractions. You slip back into hunter-gatherer mode—and when you do, you’re capable of remarkable things. You can close your eyes and track by nose like a bloodhound, and even ride a mountain bike down a trail blindfolded and never miss a turn or hit a tree. Journalist Michael Finkel learned about human echolocation—the ability to “see” by sound, like bats—when he met Daniel Kish, a blind adventurer. Kish had his eyeballs removed when he was one year old because of a degenerative disease, but he grew up to become a skilled cyclist and solo backcountry hiker by relying on the echoes from sound waves he creates by clicking his tongue.

“He is so accomplished at echolocation that he’s able to pedal his mountain bike through streets heavy with traffic and on precipitous dirt trails,” Finkel reports. “He climbs trees. He camps out, by himself, deep in the wilderness. He’s lived for weeks at a time in a tiny cabin a two-mile hike from the nearest road. He travels around the globe. He’s a skilled cook, an avid swimmer, a fluid dance partner.”

Kish says his hearing isn’t special, just his listening. As proof, he holds up a pot lid. When Finkel closes his eyes and clucks, he’s surprised to find he can instantly detect the difference when Kish moves the lid closer and farther from his face. You’ve actually got more raw ability to echolocate than a bat: our mouths aren’t as suited for squeaking, but we’ve got a big advantage when it comes to interpreting echoes. “Just the auditory cortex of a human brain is many times larger than the entire brain of a bat,” Finkel points out. “This means that humans can likely process more complex auditory information than bats.”

For years, Kish has been teaching other blind students how to move in real-life ways. He sent two of them off to mountain-bike with Finkel in California’s Santa Ana Mountains. “To determine where the trail is going, and where the bushes and rocks and fence posts and trees are, the boys rely on echolocation,” Finkel notes. The riders slap their tongues against the bottom of their mouths, listen for the echoes, and form a mental image of the trail ahead—all at full speed. One “flies down the dirt trail in aerodynamic form, hands off the brakes, clicking as fast and as loud as he can,” an awestruck Finkel finds. “I try and warn them when the trail presents a serious consequence, like a long drop-off on one side or a cactus jutting out. But mostly I’m just along for the ride. It’s difficult to believe, even though it’s happening right in front of me. It’s incredible.” The only crash, in fact, is Finkel’s fault, when he hits the brakes in front of one of the blind riders and turns himself into an instant tree.

Your nose, which can detect more than a trillion distinct odors, has as much untapped ancestral power as your ears. A research team at the University of California, Berkeley, was curious to see whether humans can mimic bloodhounds and track by scent. So they blindfolded thirty-two student volunteers and had them put on earmuffs, thick gloves, and kneepads to eliminate any sensory input except smell. Then they laid out a thirty-foot trail of chocolate essence in a grassy field and turned them loose. “Two-thirds of the subjects successfully followed the scent, zigzagging back and forth across the path like a dog tracking a pheasant,” the researchers reported in Nature Neuroscience. With zero training, most of them did well; with a little practice, they were great. Their tracking speed more than doubled after a few days, and that was just the tip of their potential. “Longer-term training would lead to further increases in tracking velocity,” the researchers noted.

Yale University neuroscientist Dr. Gordon Shepherd had the money quote when he learned of the experiment: “If we go back on our four legs and get down on the ground, we may be able to do things we had no idea we could do.” Seeing in the dark, tracking prey by nose—today they sound like superpowers, but for two million years, they were just survival. We haven’t lost the natural strengths that made us the most formidable creatures on the planet. We might just need the Natural Method to wake them up.

On Itacaré’s beach that morning, Erwan Le Corre hoists a rock about the size of a watermelon and passes it to Serginho, who pivots and hands it to me. I swing it into the hands of the guy beside me as Erwan hands Serginho another rock, then another, until there are five in play and it’s all I can do to get one rock out of my hands before the next is shoved into my gut. Unlike medicine balls, which always have the same, easily graspable shape, the unpredictable size and weight of rocks forces you to focus intensely on grip and balance. Even though the rocks are slickening with sweat and my arms are burning, I’m desperate not to be the first to let one slip. Luckily, just when I’m in danger of smashing my toes, Erwan raises a hand for us to stop. I drop my rock, relieved—until I find out what’s up next.

He pairs us off for Erwan-style wind sprints: Each of us has to hoist another guy across our shoulders in a rescue hold and race in and out of the knee-high surf. If there’s a more nerve-racking workout than preventing a 220-pound Thai fighter from falling on your head while you’re sprinting through churning water, I don’t want to know about it. Humans are heavy and lumpy and oddly balanced, forcing you to constantly adjust your posture, footing, handholds, and core. Keeping control of a body on your back, as I soon learn, demands intense concentration.

Next Erwan has a pile of six-foot-long driftwood poles at the ready. The other guys know what to expect and start trotting down the beach. As they pass Erwan, he tosses some of them a pole. He tosses the last one to me, then takes off on a run with his hands outstretched. I toss it back, and he immediately flips it toward me again, this time a little ahead so I have to accelerate. We cross the entire beach this way, mixing up our throws, totally absorbed in our run-’n’-gun until I notice we’re about to crash into the rocks. Without breaking stride, Erwan flips the stick around, plants it in the sand, and pole-vaults up onto the boulders.