Deep Freediving, renegade science, and what the ocean tells us about ourselves

Review by New York Times Review

HOW, IN THIS age of surveillance, can we lose a 210-foot airplane? With its known initial flight path and fuel load, investigators can restrict the last possible position of Malaysia Airlines Flight 370 to a sliver of the globe. Trouble is, most of that sliver - like 71 percent of Earth's surface - is covered by water. The difficulty of finding a Boeing 777 can serve as a symbol of how little we know about the portion of our planet that lies beneath the surface of the ocean. Had Flight 370 crashed into the moon or Mars, we would have found it by now, because we have better maps of those desiccated surfaces than of our own planet. The ocean's opacity makes James Nestor's mission in "Deep: Freediving, Renegade Science, and What the Ocean Tells Us About Ourselves" particularly ambitious: to see the sea, from surface eddies to fathomless trenches. The underwater travelogue begins near the ocean's surface, where Nestor's tour guides are competitors at the world freediving championship. Competitive freediving, Nestor quickly makes clear, is a ridiculous sport. Divers hold their breath and see how low they can go without suffering grievous harm. Top divers submerge for more than three minutes and reach depths below 300 feet, where pressure causes human lungs to "shrink to the size of two baseballs," Nestor writes. At first intrigued, Nestor quickly becomes disgusted as one diver after another surfaces with blood pouring from their noses, or dragged unconscious by rescue divers or in cardiac arrest. (In November, The New York Times ignited a public discussion of journalistic ethics with a photo of bulging-eyed Nicholas Mevoli moments after he emerged from a freedive record attempt and just before he blacked out and died.) When practiced outside the structure of competition and the reckless chasing of depth records, however, freediving can be practical, even beautiful. Nestor meets researchers who freedive in order to attach satellite transmitters to sharks by hand, and freediving amid marine life, Nestor writes, is "the most direct and intimate way to connect with the ocean." Nestor himself decides to learn to freedive (not competitively), and via that process unveils startling facets of human physiology, most prominently the life-preserving reflexes known as the Master Switch of Life. Human divers survive at theoretically fatal pressures because of a reflexive retreat of blood from the extremities to the vital organs, which keeps the brain and heart flush with oxygen and the lungs engorged with enough blood to prevent collapse. Humans exposed to high pressure on land fail to flip the Master Switch. It is, then, a purely submarine aspect of our biology. Divers who learn to cultivate it, as Nestor does, can go up and down rapidly and stay submerged for several minutes. Deep into "Deep," in the most suspenseful narrative moment, Nestor freedives with sperm whales, a mother "the size of a school bus" and her "short bus"-size calf. "They look like landmasses," Nestor writes, "submerged islands." His fear is palpable, and rational. Playful whale roughhousing - like slapping a diver with a 12-foot tail fluke - tends to go poorly for the smaller mammal in the encounter. Nestor stays still as the whales approach to within 30 feet and shower him in a fusillade of écholocation clicks. The signals that the whales receive from rebounding sound waves allow them to assay another animal, and to image the innards, like a waterborne version of X-rays. "The clicks now sound like jackhammers on pavement," Nestor writes, as the water around him vibrates with energy. The whales "are scanning us inside and out." Apparently satisfied with Nestor's organs, the whales then switch to a short, patterned series of "coda clicks," thought to be a personal signature. The whales, it seems, are identifying themselves. Afterward, they slip back into the wavering shadows, "and the ocean, once again, falls silent." While the scientific claims of freediving researchers can be specious - "pretty flimsy scientific cover to go swimming with whales," as one scientist puts it - Nestor's awe-inspiring encounter is made possible only because he learns how to stay underwater for extended periods. Next to the ocean itself, and Nestor, the Master Switch is the most important character in "Deep." It is the apotheosis of the evolutionary connections of humans to marine life that Nestor enumerates, from the ability of blind people (and dolphins and whales) to use écholocation, to evidence that humans (like sharks) might have a navigational instinct predicated on Earth's magnetic field. On very rare occasions, Nestor stretches the human-marine connection. He writes of "sea creatures with whom we share a great deal of DNA," an insight that is meaningful only in an extremely superficial genetic context. But that is a drop in Nestor's wondrous ocean. There is a point about 30 feet below the surface that freedivers know as "neutral buoyancy." Beneath it, the ocean stops trying to spit you out and begins sucking you in. That is how "Deep" itself unfolds. THE FIRST TWO CHAPTERS, "0" and "-60" - corresponding to the depths they explore - are in freedive range. Much beneath that, freedivers are limited in what they can see, so Nestor travels the world meeting scientists and explorers who can reveal what is below. The deeper the book ventures into the ocean, the more dramatic and unusual the organisms therein and the people who observe them. Nestor takes a harrowing ride to -2,500 feet with one D.I.Y. submarine builder from New Jersey. The man operates his vessel in Honduras because "taking tourists down 70 stories in a homemade, unlicensed submarine, without insurance, was a liability nightmare," and regulations in Honduras are "lax or nonexistent." It adds to the drama when they reach the "midnight zone" - where light ceases to penetrate the water and some organisms have evolved into hermaphrodites to double their chance of bumping into a potential mate - and the hull of the bubble-gum-and-duct-tape sub begins creaking and fizzing. The final chapter is "-28,700," the hadal zone - named for Hades, the Greek mythological underworld - where the environment is alien enough that it could be on some other planet circling some other star. And yet, there is only one thing that all life on earth requires: not sunlight, not even oxygen, but water. The abyssal depths are crawling with organisms that have followed unique evolutionary paths for millions of years. "It's as if," Nestor writes in his precise prose, "there were an archipelago of Galápagos Islands buried beneath five miles of black ocean." There are four-inch-wide, single-celled xenophyophores; "albino shrimp the size of a house cat" ; fish with "fins shaped like bird wings and ... vibration sensors on their heads." In fact, the deep ocean appears to have the greatest biodiversity of any habitat on earth, but most of it remains unknown. Whenever a net is dropped below 3,000 feet, a majority of species dragged up with it have never been seen before. In the epilogue, "Ascents," Nestor comes back up through the depths, rapidly enough to give the reader a version of the bends, but it serves as a beautiful construct allowing him to revisit "Deep's" dramatis personae. It's the finale of Nestor's reportorial trip down to Hades and back again. Through his eyes and his stories, it's a journey well worth taking. There is only one thing that all life requires: not sunlight, not even oxygen, but water. DAVID EPSTEIN'S first book, "The Sports Gene: Inside the Science of Extraordinary Athletic Performance," came out in paperback in April.

Copyright (c) The New York Times Company [June 15, 2014]

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Review by Booklist Review

*Starred Review* The ocean, journalist Nestor reminds us, is the final unseen, untouched, and undiscovered wilderness. It is also a frontier extremely difficult to explore. The pressure is so intense, at 30 feet down our lungs collapse to half their normal size. Yet Nestor watches divers descend to 300 feet without scuba gear at a freediving competition. Alarmed (the consequences can be dire) and intrigued, Nestor sets out to learn about the allure and best purpose of freediving as a tool to help crack the ocean's mysteries, thus launching an exceptionally dramatic and revelatory inquiry. As he begins training as a freediver, in spite of his fears, Nestor learns about our body's remarkable amphibious reflexes, instantaneous physical transformations used for centuries by pearl divers. Now innovative and daring marine explorers use freediving to swim among sharks, dolphins, and whales. Their mind-blowing discoveries about how these denizens of the deep navigate and communicate in the watery dark are matched by findings that prove that we, too, can practice echolocation and orient ourselves via our innate magnetic sense of direction, natural abilities our ancestors used long before maps and GPS. With a wow on every page, and brimming with vivid portraits, lucid scientific explanations, gripping (and funny) first-person accounts, and urgent facts about the ocean's endangerment, Nestor's Deep is galvanizing, enlightening, and invaluable.--Seaman, Donna Copyright 2014 Booklist

From Booklist, Copyright (c) American Library Association. Used with permission.

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Review by Publisher's Weekly Review

This exploration of the "human connection to the ocean" begins with free diving, the technique of depth diving on single breaths of air. While free diving may have earned YouTube notoriety as a danger-laden sport with "fringe disciplines" and stunning depth records, Nestor is only briefly fascinated by the "ego-driven competition," and focuses instead on free diving as the elemental mode for accessing the wonders of the ocean. A surfer with a lifelong connection to the ocean, Nestor interpolates his own training to "go deep" with encounters with scientists researching at the limits of ocean knowledge. He avoids the "quasi-religious terms" encountered in others' experiences of deep dives, yet still offers an acute sense of wonder and respect for the ocean, from the disappearing diving traditions of ancient cultures to the diversity of life in earth's deepest trenches. Nestor's explorations of the "outer limits of amphibious abilities" and "latent and unconscious senses" that link humans to our aquatic evolutionary heritage make for a thrilling account, made timely by the rapidly changing state of earth's most expansive environment. Agent: Danielle Svetcov. (July) (c) Copyright PWxyz, LLC. All rights reserved.

(c) Copyright PWxyz, LLC. All rights reserved

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Review by Library Journal Review

Competitive freediving is an extreme sport that tests one's limits and fights one's natural instincts. Diving without any scuba gear to depths of up to 300 feet all in one breath can result in resurfacing unconscious, paralyzed, bloody, or dead. The author, a journalist, adventurer and traveler labels it the most dangerous sport on earth. Although practiced for centuries by pearl, coral, and sponge divers, these groups had an economic purpose. A party with whom the author associated in his travels to Central America and the South Pacific uses -freediving as a vehicle to learn about whale and shark navigation and communication. They are scientific amateurs without academic credentials but with great curiosity and love of the ocean. Chapters are arranged by increasing depths (minus 60 feet, minus 300 feet, etc.) and include trips the author made in a homemade sub-marine that submerged beyond 2,500 feet. A melange of facts about hydrothermal vent animals; the underwater habitat Aquarius in Key Largo, FL; bioluminescence; and marine geology are presented by the author, whose articles have appeared in the New York Times, San Francisco Chronicle, and Salon. This reviewer found no other books on the subject. VERDICT This well-written title will either fascinate or repel readers with its discussions of marine life on the one hand and the horrific descriptions of the masochistic sport of freediving. Photos not seen.-Judith B. Barnett, Univ. of Rhode Island Lib., Kingston (c) Copyright 2014. Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

(c) Copyright Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

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Review by Kirkus Book Review

Nestor (Get High Now (without drugs), 2009, etc.) takes readers around the world as he explores the ocean's mysterious and revealing depthsand what the deep might reveal about mankind's origin and future.We've all seen documentary footage of strange deep-sea creatures, trundling along a hazy ocean floor, maybe even glowing in the dark. But how much do we really know about these ecosystems, and how much have we forgotten about our own profound connection to the ocean? With verve and humor, the author describes his own risk-taking attempts to understand the ocean's ancient secrets and future potential and the daring and brilliant people who have dedicated their lives to probing deeper. Take free diving, for example: Historical accounts suggest that humans have been diving hundreds of feet deep for centuries, with no equipment and holding just one breath of air. Our bodies are capable of withstanding the crushing pressure in deep water, and we have a built-in instinct called the "master switch of life" that activates to give human bodies amphibious skills. Nestor goes into great detail about his own free-dive training, and his writing is sharp, colorful and thrilling. Equally magnetic is the account of his adventure in a deep-sea submarine, a cramped contraption that dove to 2,600 feet below the surface, where light can't penetrate the water but a variety of organisms thrive. Perhaps the most memorable chapter covers the author's experience diving with sperm whales, whose enigmatic vocalizations may be the most complex language we can imagine. Throughout, scientific mini-lessons and lively character profiles give context to the author's anecdotes, bringing the ocean to life from a research perspective as well as a human one.An adventurous and frequently dazzling look at our planet's most massive habitat. Copyright Kirkus Reviews, used with permission.

Copyright (c) Kirkus Reviews, used with permission.

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0 I'm a guest here, a journalist covering a sporting event that few people have heard of: the world freediving championship. I'm sitting at a cramped desk in a seaside hotel room that overlooks a boardwalk in the resort town of Kalamata, Greece. The hotel is old and shows it in the cobweb cracks along the walls, threadbare carpet, and dirt shadows of framed pictures that once hung in dim hallways. I've been sent here by Outside magazine, because the 2011 Individual Depth World Championship is a milestone for competitive freediving--the largest gathering of athletes in the history of the little-known sport. Since I've lived my whole life by the ocean, still spend much of my free time in it, and often write about it, my editor thought I'd be a good fit for the assignment. What he didn't know was that I had only a superficial understanding of freediving. I hadn't done it, didn't know anyone who had, and had never seen it before. I spend my first day in Kalamata reading up on the competition rules and the sport's rising stars. I'm not impressed. I Google through photographs of competitive freedivers in mermaid outfits, flashing hang-loose signs while floating upside down in the water, and blowing intricate bubble rings from the bottom of a swimming pool. It seems like the kind of oddball hobby people take up, like badminton or Charleston dancing, so they can talk about it at cocktail parties and refer to it in their e-mail handles. Nonetheless, I have a job to do. At five thirty the following morning, I'm at the Kalamata marina talking my way onto a twenty-seven-foot sailboat that belongs to a scruffy Quebecois expat. His is the only spectator boat allowed out at the competition, which is held in the deep open waters about ten miles from the Kalamata marina. I'm the only journalist aboard. By 8:00 a.m., we've tied up to a flotilla of motorboats, platforms, and gear that serves as the competitors' jumping-off point. The divers in the first group arrive and take positions around three yellow ropes dangling off a nearby platform. An official counts down from ten. The competition begins. What I see next will confound and terrify me. I watch as a pencil-thin New Zealander named William Trubridge swallows a breath, upends his body, and kicks with bare feet into the crystalline water below. Trubridge struggles through the first ten feet, heaving broad strokes. Then, at about twenty feet, his body loosens, he places his arms by his sides in a skydiver pose, and he sinks steadily deeper until he vanishes. An official watching a sonar screen at the surface follows his descent, ticking off distances as he goes down: "Thirty meters . . . forty meters . . . fifty meters." Trubridge reaches the end of the rope, some three hundred feet down, turns around, and swims back toward the surface. Three agonizing minutes later, his tiny figure rematerializes in the deep water, like a headlight cutting through fog. He pops his head up at the surface, exhales, takes a breath, flashes an okay sign to an official, then gets out of the way to make room for the next competitor. Trubridge just dove thirty stories down and back, all on one lungful of air--no scuba gear, air tube, protective vest, or even swim fins to assist him. The pressure at three hundred feet down is more than ten times that of the surface, strong enough to crush a Coke can. At thirty feet, the lungs collapse to half their normal size; at three hundred feet, they shrink to the size of two baseballs. And yet Trubridge and most of the other freedivers I watch on the first day resurface unscathed. The divers don't look forced either, but natural, as if they all really belong down there. As if we all do. I'm so dazzled by what I see that I need to tell somebody immediately. I call my mother in Southern California. She doesn't believe me. "It's impossible," she says. After we talk about it, she dials some friends of hers who've been avid scuba divers for forty years and then calls me back. "There is an oxygen tank at the seafloor or something," she says. "And I suggest you do your research before publishing any of this." But there was no oxygen tank at the end of the rope, and if there had been, and if Trubridge and the other divers had actually breathed some of it before ascending, their lungs would have exploded when the air from the tank expanded in the shallower depths, and their blood would have bubbled with nitrogen before they reached the surface. They'd die. The human body can withstand the pressures of a fast three-hundred-foot underwater ascent only in its natural state. Some humans handle it better than others. Over the next four days, I watch several more competitors attempt dives to around three hundred feet. Many can't make it and turn back. They resurface with blood running down their faces from their noses, unconscious, or in cardiac arrest. The competition just keeps going on. And, somehow, this sport is legal. For most of this group, attempting to dive deeper than anyone--even scientists--ever thought possible is worth the risk of paralysis or death. But not for all of them. I meet a number of competitors who approach freediving with a more sane outlook. They aren't interested in the face-off with mortality. They don't care about breaking records or beating the other guy. They freedive because it's the most direct and intimate way to connect with the ocean. During that three minutes beneath the surface (the average time it takes to dive a few hundred feet), the body bears only a passing resemblance to its terrestrial form and function. The ocean changes us physically, and psychically. In a world of seven billion people, where every inch of land has been mapped, much of it developed, and too much of it destroyed, the sea remains the final unseen, untouched, and undiscovered wilderness, the planet's last great frontier. There are no mobile phones down there, no e-mails, no tweeting, no twerking, no car keys to lose, no terrorist threats, no birthdays to forget, no penalties for late credit card payments, and no dog shit to step in before a job interview. All the stress, noise, and distractions of life are left at the surface. The ocean is the last truly quiet place on Earth. These more philosophical freedivers get a glassy look in their eyes when they describe their experiences; it's the same look one sees in the eyes of Buddhist monks or emergency room patients who have died and then been resuscitated minutes later. Those who have made it to the other side. And best of all, the divers will tell you, "It's open to everyone." Literally everyone--no matter your weight, height, gender, or ethnicity. The competitors gathered in Greece aren't all the toned, superhuman Ryan Lochte-type swimmers you might expect. There are a few impressive physical specimens, like Trubridge, but also chubby American men, tiny Russian women, thick-necked Germans, and wispy Venezuelans. Freediving flies in the face of everything I know about surviving in the ocean; you turn your back on the surface, swim away from your only source of air, and seek out the cold, pain, and danger of deep waters. Sometimes you pass out. Sometimes you bleed out of your nose and mouth. Sometimes you don't make it back alive. Other than BASE jumping--parachuting off buildings, antennas, spans (bridges), and earth (geological formations)--freediving is the most dangerous adventure sport in the world. Dozens, perhaps hundreds, of divers are injured or die every year. It seems like a death wish. And yet, days later, after I return home to San Francisco, I can't stop thinking about it. I begin to research freediving and the claims made by competitors about the human body's amphibious reflexes. What I find--what my mother would never believe and what most people would doubt--is that this phenomenon is real, and it has a name. Scientists call it the mammalian dive reflex or, more lyrically, the Master Switch of Life, and they've been researching it for the past fifty years. The term Master Switch of Life , which was coined by physiologist Per Scholander in 1963, refers to a variety of physiological reflexes in the brain, lungs, and heart, among other organs, that are triggered the second we put our faces in water. The deeper we dive, the more pronounced the reflexes become, eventually spurring a physical transformation that protects our organs from imploding under the immense underwater pressure and turns our bodies into efficient deep-sea-diving systems. Freedivers can anticipate these switches and exploit them to dive deeper and longer. Ancient cultures knew all about the Master Switch and employed it for centuries to harvest sponges, pearls, coral, and food hundreds of feet below the surface of the ocean. European visitors to the Caribbean, Middle East, Indian Ocean, and South Pacific in the seventeenth century reported seeing locals dive down more than one hundred feet and stay there for up to fifteen minutes on a single breath. But most of these reports are hundreds of years old, and whatever secret knowledge of deep diving these cultures harbored has been lost to the ages. I begin to wonder: If we've forgotten an ability as profound as deep diving, what other reflexes and skills have we lost? Excerpted from Deep: Freediving, Renegade Science, and What the Ocean Tells Us about Ourselves by James Nestor All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.

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