18 THE BOUNDING MAIN

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    IMAGIRYING TO live in a world dominated by dihydrogen oxide, a pound that hasno taste or smell and is so variable in its properties that it is generally benign but at othertimes swiftly lethal. Depending on its state, it  scald you or freeze you. In the presence ofcertain anic molecules it  form carbonic acids so nasty that they  strip the leavesfrom trees ahe faces off statuary. In bulk, when agitated, it  strike with a fury thatno human edifice could withstand. Even for those who have learo live with it, it is anoften murderous substance. We call it water.

    Water is everywhere. A potato is 80 pert water, a cow 74 pert, a bacterium 75pert. A tomato, at 95 pert, is little but water. Even humans are 65 pert water,making us more liquid than solid by a margin of almost two to one. Water is strauff. It isformless and transparent, a we long to be beside it. It has no taste a we love thetaste of it. We will travel great distances and pay small fortuo see it in sunshine. Ahough we know it is dangerous and drowns tens of thousands of people every year, we’t wait to froli it.

    Because water is so ubiquitous we tend to overlook what araordinary substa is.

    Almost nothing about it  be used to make reliable predis about the properties of otherliquids and vice versa. If you knew nothing of water and based your assumptions on thebehavior of pounds most chemically akin to it—hydrogen selenide or hydrogen sulphidenotably—you would expect it to boil at minus 135 degrees Fahre and to be a gas at roomtemperature.

    Most liquids when chilled tract by about 10 pert. Water does too, but only down to apoint. O is within whispering distance of freezing, it begins—perversely, beguilingly,extremely improbably—to expand. By the time it is solid, it is almost a tenth morevoluminous than it was before. Because it expands, ice floats on water—“an utterly bizarreproperty,” acc to John Gribbin. If it lacked this splendid waywardness, ice would sink,and lakes and os would freeze from the bottom up. Without surface ice to hold heat ier’s warmth would radiate away, leaving it even chillier and creati more ice.

    Soohe os would freeze and almost certainly stay that way for a very long time,probably forever—hardly the ditions to nurture life. Thankfully for us, water seemsunaware of the rules of chemistry or laws of physics.

    Everyone knows that water’s chemical formula is H2O, which means that it sists of onelargish oxygen atom with two smaller hydrogen atoms attached to it. The hydrogen atomsg fiercely to their oxygen host, but also make casual bonds with other water molecules.

    The nature of a water molecule means that it engages in a kind of dah other watermolecules, briefly pairing and then moving on, like the ever-ging partners in a quadrille,to use Robert Kunzig’s nice phrase. A glass of water may not appear terribly lively, but everymolecule in it is ging partners billions of times a sed. That’s why water moleculesstick together to form bodies like puddles and lakes, but not so tightly that they ’t be easilyseparated as when, for instance, you dive into a pool of them. At any given moment only 15pert of them are actually toug.

    In one sehe bond is very strong—it is why water molecules  flow uphill whensiphoned and why water droplets on a car hood show such a singular determination to beadwith their partners. It is also why water has surface tension. The molecules at the surface areattracted more powerfully to the like molecules beh and beside them than to the airmolecules above. This creates a sort of membrarong enough to support is andskipping stones. It is what gives the sting to a belly flop.

    I hardly need point out that we would be lost without it. Deprived of water, the human bodyrapidly falls apart. Within days, the lips vanish “as if amputated, the gums bla, the hers to half its length, and the skin so tracts around the eyes as to prevent blinking.”

    Water is so vital to us that it is easy to overlook that all but the smallest fra of the wateroh is poisonous to us—deadly poisonous—because of the salts within it.

    We need salt to live, but only in very small amounts, aer tains way more—about seventy times more—salt than we  safely metabolize. A typical liter of seawater willtain only about 2.5 teaspoons of on salt—the kind we sprinkle on food—but muchlarger amounts of other elements, pounds, and other dissolved solids, which arecollectively known as salts. The proportions of these salts and minerals in our tissues isunily similar to seawater—we sweat and cry seawater, as Margulis and Sagan have putit—but curiously we ot tolerate them as an input. Take a lot of salt into your body andyour metabolism very quickly goes into crisis. From every cell, water molecules rush off likeso many volunteer firemen to try to dilute and carry off the sudden intake of salt. This leavesthe cells dangerously short of the water they o carry out their normal funs. Theybee, in a word, dehydrated. Ireme situations, dehydration will lead to seizures,unsciousness, and brain damage. Meanwhile, the overworked blood cells carry the salt tothe kidneys, which eventually bee overwhelmed and shut down. Without funingkidneys you die. That is why we don’t drier.

    There are 320 million cubic miles of water oh and that is all we’re ever going to get.

    The system is closed: practically speaking, nothing  be added or subtracted. The water youdrink has been around doing its job sihe Earth was young. By 3.8 billion years ago, theos had (at least more or less) achieved their present volumes.

    The water realm is known as the hydrosphere and it is overwhelmingly oiiy-seven pert of all the water oh is in the seas, the greater part of it in the Pacific, whichcovers half the pla and is bigger than all the landmasses put together. Altogether thePacific holds just over half of all the o water (51.6 pert to be precise); the Atlantic has23.6 pert and the Indian O 21.2 pert, leaving just 3.6 pert to be ated forby all the other seas. The average depth of the o is 2.4 miles, with the Pacifi averageabout a thousa deeper thalantid Indian Os. Altogether 60 pert ofthe pla’s surface is o more than a mile deep. As Philip Ball notes, we would better callour pla h but Water.

    Of the 3 pert of Earth’s water that is fresh, most exists as ice sheets. Only the tiamount—0.036 pert—is found in lakes, rivers, and reservoirs, and an even smaller part—just 0.001 pert—exists in clouds or as vapor. Nearly 90 pert of the pla’s ice is inAntarctica, and most of the rest is in Greenland. Go to the South Pole and you will bestanding on nearly two miles of ice, at the North Pole just fiftee of it. Antarctica alonehas six million cubic miles of iough to raise the os by a height of two hundred feetif it all melted. But if all the water imosphere fell as rain, evenly everywhere, theos would deepen by only an inch.

    Sea level, ially, is an almost entirely notional cept. Seas are not level at all.

    Tides, winds, the Coriolis force, and other effects alter water levels siderably from oo another and within os as well. The Pacific is about a foot and a half higher alongits western edge—a sequence of the trifugal force created by the Earth’s spin. Just aswhen you pull on a tub of water the water tends to flow toward the other end, as if relut toe with you, so the eastward spin of Earth piles water up against the o’s westernmargins.

    sidering the age-old importance of the seas to us, it is striking how long it took theworld to take a stifiterest in them. Until well into the eenth tury most of whatwas known about the os was based on what washed ashore or came up in fishis,and nearly all that was written was based more oe and supposition than on physicalevidence. In the 1830s, the British naturalist Edward Forbes surveyed o beds throughoutthe Atlantid Mediterranean and declared that there was no life at all in the seas below2,000 feet. It seemed a reasonable assumption. There was no light at that depth, so no plantlife, and the pressures of water at such depths were known to be extreme. So it came assomething of a surprise when, in 1860, one of the first transatlantic telegraph cables washauled up for repairs from more than two miles down, and it was found to be thicklyencrusted with corals, clams, and other livius.

    The first really anized iigation of the seas didn’t e until 1872, when a jointexpeditioween the British Museum, the Royal Society, and the British gover setforth from Portsmouth on a former warship called HMS Challenger. For three and a halfyears they sailed the world, sampling waters, ing fish, and hauling a dredge throughsediments. It was evidently dreary work. Out of a plement of 240 stists and crew, onein four jumped ship a more died or went mad—“driven to distra by the mind-numbing routine of years ing” in the words of the historian Samantha Weinberg. Butthey sailed across almost 70,000 nautical miles of sea, collected over 4,700 new species ofmarine anisms, gathered enough information to create a fifty-volume report (which tookeen years to put together), and gave the world the name of a new stific discipline:

    oography. They also discovered, by means of depth measurements, that there appeared tobe submerged mountains in the mid-Atlantic, prompting some excited observers to speculatethat they had found the lost ti of Atlantis.

    Because the institutional world mostly ighe seas, it fell to devoted—and veryoccasional—amateurs to tell us what was down there. Modern deep-water exploration beginswith Charles William Beebe and Otis Barton in 1930. Although they were equal partners, themore colorful Beebe has always received far more written attention. Born in 1877 into a well-to-do family in New York City, Beebe studied zoology at bia Uy, then took ajob as a birdkeeper at the New York Zoological Society. Tiring of that, he decided to adoptthe life of an adventurer and for the  quarter tury traveled extehrough Asiaand South America with a succession of attractive female assistants whose jobs wereiively described as “historian and teicist” or “assistant in fish problems.” Hesupported these endeavors with a succession of popular books with titles like Edge of theJungle and Jungle Days, though he also produced some respectable books on wildlife andornithology.

    In the mid-1920s, on a trip to the Galápagos Islands, he discovered “the delights ofdangling,” as he describ<dfn></dfn>ed deep-sea diving. Soon afterward he teamed up with Barton, whocame from an evehier family, had also attended bia, and also longed foradventure. Although Beebe nearly always gets the credit, it was in fact Barton who desighe first bathysphere (from the Greek word for “deep”) and fuhe $12,000 cost of itsstru. It was a tiny and necessarily robust chamber, made of cast iron 1.5 ihid with two small portholes taining quartz blocks three ihick. It held two men, butonly if they were prepared to bee extremely well acquainted. Even by the standards of theage, the teology was unsophisticated. The sphere had no maneuverability—it simply hungon the end of a long cable—and only the most primitive breathing system: to ralize theirown carbon dioxide they set out open s of soda lime, and to absorb moisture they opened asmall tub of calcium chloride, over which they sometimes waved palm fronds to encechemical reas.

    But the nameless little bathysphere did the job it was inteo do. On the first dive, inJune 1930 in the Bahamas, Barton and Beebe set a world record by desding to 600 feet. By1934, they had pushed the record to 3,028 feet, where it would stay until after the war. Bartonwas fident the device was safe to a depth of 4,500 feet, though the strain on every bolt andrivet was audibly evident with each fathom they desded. At ah, it was brave andrisky work. At 3,000 feet, their little porthole was subjected to een tons of pressure persquare inch. Death at such a depth would have been instantaneous, as Beebe never failed toobserve in his many books, articles, and radio broadcasts. Their main , however, wasthat the shipboard winch, straining to hold on to a metal ball and two tons of steel cable,would snap ahe two men plunging to the seafloor. In su event, nothing couldhave saved them.

    The ohing their dests didn’t produce was a great deal of worthwhile sce.

    Although they entered many creatures that had not been seen before, the limits ofvisibility and the fact that her of the intrepid aquanauts was a trained oographer meantthey often weren’t able to describe their findings in the kind of detail that real stistscraved. The sphere didn’t carry aernal light, merely a 250-watt bulb they could hold upto the window, but the water below five hundred feet ractically imperable anyway,and they were peering into it through three inches of quartz, so anything they hoped to viewwould have to be nearly as ied in them as they were in it. About all they could report, insequence, was that there were a lot of strahings down there. On one dive in 1934,Beebe was startled to spy a giant serpent “more thay feet long and very wide.” Itpassed too swiftly to be more than a shadow. Whatever it was, nothing like it has been seenby anyone since. Because of such vagueheir reports were generally ignored byacademics.

    After their record-breaking dest of 1934, Beebe lost i in diving and moved on toother adventures, but Barton persevered. To his credit, Beebe always told anyone who askedthat Barton was the real brains behind the enterprise, but Barton seemed uo step fromthe shadows. He, too, wrote thrilling ats of their uer adventures and even starredin a Hollywood movie called Titans of the Deep, featuring a bathysphere and maingand largely fialized enters with aggressive giant squid and the like. He eveised Camel cigarettes (“They don’t give me jittery nerves”). In 1948 he increased thedepth record by 50 pert, with a dive to 4,500 feet in the Pacific O near California, butthe world seemed determio overlook him. One neer reviewer of Titans of the Deepactually thought the star of the film was Beebe. Nowadays, Barton is lucky to get a mention.

    At all events, he was about to be prehensively eclipsed by a father-and-son team fromSwitzerland, Auguste and Jacques Piccard, who were designing a ype of probe called abathyscaphe (meaning “deep boat”). Christerieste, after the Italian city in which it wasbuilt, the new device maneuvered indepely, though it did little more than just go up anddown. On one of its first dives, in early 1954, it desded to below 13,287 feet, nearly threetimes Barton’s record-breaking dive of six years earlier. But deep-sea dives required a greatdeal of costly support, and the Piccards were gradually going broke.

    In 1958, they did a deal with the U.S. Navy, which gave the Navy ownership but left themin trol. Now flush with funds, the Piccards rebuilt the vessel, giving it walls five ihid shrinking the windows to just two inches in diameter—little more than peepholes.

    But it was now strong enough to withstand truly enormous pressures, and in January 1960Jacques Piccard and Lieutenant Don Walsh of the U.S. Navy sank slowly to the bottom of theo’s deepest yon, the Mariana Trench, some 250 miles off Guam in the western Pacifid discovered, not ially, by Harry Hess with his fathometer). It took just under fourhours to fall 35,820 feet, or almost seven miles. Although the pressure at that depth wasnearly 17,000 pounds per square inch, they noticed with surprise that they disturbed a bottom-dwelling flatfish just as they touched down. They had no facilities for taking photographs, sothere is no visual record of the event.

    After just twenty mi the world’s deepest point, they returo the surface. It wasthe only occasion on which human beings have gone so deep.

    Forty years later, the question that naturally occurs is: Why has no one gone back siobegin with, further dives were vigorously opposed by Vice Admiral Hyman G. Rickover, aman who had a lively temperament, forceful views, and, most pertily, trol of thedepartmental checkbook. He thought uer exploration a waste of resources and poi that the Navy was not a researstitute. The nation, moreover, was about to beefully preoccupied with space travel and the quest to send a man to the Moon, which madedeep sea iigations seem unimportant and rather old-fashioned. But the decisivesideration was that the Trieste dest didn’t actually achieve much. As a Navy officialexplained years later: “We didn’t learn a hell of a lot from it, other than that we could do it.

    Why do it again?” It was, in short, a long way to go to find a flatfish, and expeoo.

    Repeating the exercise today, it has beeimated, would cost at least $100 million.

    When uer researchers realized that the Navy had no iion of pursuing apromised exploratiram, there ained outcry. Partly to placate its critics, theNavy provided funding for a more advanced submersible, to be operated by the Woods HoleOographistitution of Massachusetts. Called Alvin, in somewhat tracted honor ofthe oographer Allyn C. Vi would be a fully maneuverable minisubmarihough itwouldn’t go anywhere near as deep as the Trieste. There was just one problem: the designerscouldn’t find anyone willing to build it. Acc to William J. Broad in The UniverseBelow: “No big pany like General Dynamics, which made submarines for the Navy,wao take on a project disparaged by both the Bureau of Ships and Admiral Rickover, thegods of naval patronage.” Eventually, not to say improbably, Alvin was structed byGeneral Mills, the food pany, at a factory where it made the maes to producebreakfast cereals.

    As for what else was down there, people really had very little idea. Well into the 1950s, thebest maps available <cite>.</cite>to oographers were overwhelmingly based on a little detail fromscattered surveys going back to 1929 grafted onto, essentially an o of guesswork. TheNavy had excellent charts with which to guide submarihrough yons and aroundguyots, but it didn’t wish suformation to fall into Soviet hands, so it kept its knowledgeclassified. Academics therefore had to make do with sketchy and antiquated surveys or relyon hopeful surmise. Even today our knowledge of the o floors remains remarkably lowresolution. If you look at the Moon with a standard backyard telescope you will seesubstantial craters—Fracastorious, Blanus, Zach, Planck, and many others familiar to anylunar stist—that would be unknown if they were on our own o floors. We have bettermaps of Mars than we do of our own seabeds.

    At the surface level, iigative teiques have also been a trifle ad ho 1994, thirty-four thousand ice hockey gloves were swept overboard from a Korean cargo ship during astorm in the Pacific. The gloves washed up all over, from Vancouver to Vietnam, helpingoographers to trace currents more accurately than they ever had before.

    Today Alvin is nearly forty years old, but it still remains America’s premier research vessel.

    There are still no submersibles that  go anywhere he depth of the Mariana Trend only five, including Alvin, that  reach the depths of the “abyssal plain”—the deepo floor—that covers more than half the pla’s surface. A typical submersible costsabout $25,000 a day to operate, so they are hardly dropped into the water on a whim, still lessput to sea in the hope that they will randomly stumble on something of i. It’s rather asif our firsthand experience of the surface world were based on the work of five guys explon garden tractors after dark. Acc to Robert Kunzig, humans may have scrutinized“perhaps a millionth or a billionth of the sea’s darkness. Maybe less. Maybe much less.”

    But oographers are nothing if not industrious, and they have made several importantdiscoveries with their limited resources—including, in 1977, one of the most important andstartling biological discoveries of the tweh tury. In that year Alvin found teemingies of large anisms living on and around deep-sea vents off the Galápagos Islands—tube worms over te long, clams a foot wide, shrimps and mussels in profusiling spaghetti worms. They all owed their existeo vast ies of bacteria thatwere deriving their energy and sustenance from hydrogen sulfides—pounds profoundlytoxic to surface creatures—that were p steadily from the vents. It was a worldindepe of sunlight, oxygen, or anything else normally associated with life. This was aliving system based not on photosynthesis but on chemosynthesis, an arrahatbiologists would have dismissed as preposterous had anyone been imaginative enough tosuggest it.

    Huge amounts of heat and energy flow from these vents. Two dozen of them together willproduce as muergy as a large power station, and the range of temperatures around themis enormous. The temperature at the point of outflow  be as much as 760 degreesFahre, while a few feet away the water may be only two or three degrees above freezing.

    A type of worm called an alvinellid was found living right on the margins, with the watertemperature 140 degrees warmer at its head than at its tail. Before this it had been thought thatno plex anisms could survive in water warmer than about 130 degrees, and here wasohat was surviving warmer temperatures than that areme cold to boot. Thediscovery transformed our uanding of the requirements for life.

    It also answered one of the great puzzles of oography—something that many of usdidn’t realize uzzle—namely, why the os don’t grow saltier with time. At the riskof stating the obvious, there is a lot of salt in the sea—enough to bury every bit of land on theplao a depth of about five hundred feet. Millions of gallons of fresh water evaporate fromthe o daily, leaving all their salts behind, so logically the seas ought to grow more saltywith></a> the passing years, but they don’t. Something takes an amount of salt out of the waterequivalent to the amount being put in. For the loime, no one could figure out whatcould be responsible for this.

    Alvin’s discovery of the deep-sea vents provided the answer. Geophysicists realized that thevents were ag much like the filters in a fish tank. As water is taken down into the crust,salts are stripped from it, aually  water is blown out again through the eystacks. The process is not swift—it  take up to ten million years to  an o—but itis marvelously effit as long as you are not in a hurry.

    Perhaps nothing speaks more clearly of our psychological remoteness from the odepths than that the main expressed goal for oographers during Iional GeophysicalYear of 1957–58 was to study “the use of o depths for the dumping of radioactivewastes.” This wasn’t a secret assig, you uand, but a proud public boast. In fact,though it wasn’t much publicized, by 1957–58 the dumping of radioactive wastes had alreadybeen going on, with a certain appalling vigor, for over a decade. Since 1946, the Uateshad been ferrying fifty-five-gallon drums of radioactive gunk out to the Farallon Islands,some thirty miles off the California coast near San Francisco, where it simply threw themoverboard.

    It was all quite extraordinarily sloppy. Most of the drums were exactly the sort you seerusting behind gas stations or standing outside factories, with no protective linings of anytype. When they failed to sink, which was usually, Navy gunners riddled them with bullets tolet water in (and, of course, plutonium, uranium, and strontium out). Before it was halted inthe 1990s, the Uates had dumped many hundreds of thousands of drums into aboutfifty o sites—almost fifty thousand of them in the Farallons alone. But the U.S. was by nomeans alone. Among the other enthusiastic dumpers were Russia, a, Japan, New Zealand,and nearly all the nations of Europe.

    And what effect might all this have had on life beh the seas? Well, little, we hope, butwe actually have no idea. We are astoundingly, sumptuously, radiantly ignorant of lifebeh the seas. Even the most substantial o creatures are often remarkably little knownto us—including the most mighty of them all, the great blue whale, a creature of suchleviathan proportions that (to quote David Attenbh) its “tongue weighs as much as anelephant, its heart is the size of a car and some of its blood vessels are so wide that you couldswim down them.” It is the most gargantua that Earth has yet produced, bigger eventhan the most cumbrous dinosaurs. Yet the lives of blue whales are largely a mystery to us.

    Much of the time we have no idea where they are—where they go to breed, for instance, orwhat routes they follow to get there. What little we know of them es almost entirely fromeavesdropping on their songs, but even these are a mystery. Blue whales will sometimes breakoff a song, then pick it up again at the same spot six months later. Sometimes they strike upwith a new song, whiber  have heard before but which each already knows.

    How they do this is not remotely uood. And these are animals that must routinely eto the surface to breathe.

    For animals that need never surface, obscurity  be even more tantalizing. sider thefabled giant squid. Though nothing on the scale of the blue whale, it is a decidedly substantialanimal, with eyes the size of soccer balls and trailiacles that  reach lengths of sixtyfeet. It weighs nearly a ton and is Earth’s largest iebrate. If you du<tt></tt>mped one in a normalhousehold swimming pool, there wouldn’t be mu for anything else. Yet no stist—no person as far as we know—has ever seen a giant squid alive. Zoologists have devotedcareers t to capture, or just glimpse, living giant squid and have always failed. Theyare known mostly from being washed up on beaches—particularly, for unknown reasons, thebeaches of the South Island of New Zealand. They must exist in large numbers because theyform a tral part of the sperm whale’s diet, and sperm whales take a lot of feeding.

    1Acc to oimate, there could be as many as thirty million species of animalsliving in the sea, most still undiscovered. The first hint of how abundant life is in the deepseas didn’t e until as retly as the 1960s with the iion of the epibenthic sled, adredging device that captures anisms not just on ahe seafloor but also buried inthe sediments beh. In a single one-hour trawl along the tial shelf, at a depth of justunder a mile, Woods Hole oographers Howard Sandler and Robert Hessler ed over25,000 creatures—worms, starfish, sea cucumbers, and the like—representing 365 species.

    Even at a depth of three miles, they found some 3,700 creatures representing almost 200species anism. But the dredge could only capture things that were too slow or stupid toget out of the way. Ie 1960s a marine biologist named John Isaacs got the idea tolower a camera with bait attached to it, and found still more, in particular dense swarms ofwrithing hagfish, a primitive eel-like creature, as well as darting shoals of grenadier fish.

    Where a good food source is suddenly available—for instance, when a whale dies and sinks tothe bottom—as many as 390 species of marine creature have been found dining off it.

    Iingly, many of these creatures were found to have e from vents up to a thousandmiles distant. These included such types as mussels and clams, which are hardly known asgreat travelers. It is now thought that the larvae of certain anisms may drift through thewater until, by some unknown chemical means, they detect that they have arrived at a foodopportunity and fall onto it.

    So why, if the seas are so vast, do we so easily overtax them? Well, to begin with, theworld’s seas are not uniformly bounteous. Altogether less than a tenth of the o issidered naturally productive. Most aquatic species like to be in shallow waters where thereis warmth and light and an abundance anic matter to prime the food . Coral reefs,for instance, stitute well under 1 pert of the o’s space but are home to about 25pert of its fish.

    Elsewhere, the os aren’t nearly so rich. Take Australia. With over 20,000 miles ofcoastline and almost nine million square miles of territorial waters, it has more sea lapping itsshores than any other try, yet, as Tim Flannery notes, it doesn’t even make it into the topfifty among fishing nations. Indeed, Australia is a large  importer of seafood. This isbecause much of Australia’s waters are, like much of Australia itself, essentially desert. (Anotable exception is the Great Barrier Reef off Queensland, which is sumptuously fed.)Because the soil is poor, it produces little in the way of nutrient-rich runoff.

    Even where life thrives, it is ofteremely sensitive to disturbance. In the 1970s, fishermenfrom Australia and, to a lesser extent, New Zealand discovered shoals of a little-known fishliving at a depth of about half a mile on their tial shelves. They were known as e1The iible parts of giant squid, in particular their beaks, accumulate in sperm whales stomachs into thesubstanown as ambergris, which is used as a fixative in perfumes. The ime you spray on el No. 5(assuming you do), you may wish to reflect that you are dousing yourself in distillate of unseen sea monster.

    roughy, they were delicious, and they existed in huge numbers. In no time at all, fishing fleetswere hauling in forty thousaris hy a year. Then marine biologists madesome alarming discoveries. Roughy are extremely long lived and slow maturing. Some maybe 150 years old; any roughy you have eaten may well have been born when Victoria wasQueen. Roughy have adopted this exceedingly unhurried lifestyle because the waters they livein are so resource-poor. In such waters, some fish spawn just on a lifetime. Clearly theseare populations that ot stand a great deal of disturbance. Unfortunately, by the time thiswas realized the stocks had been severely depleted. Even with careful ma it will bedecades before the populations recover, if they ever do.

    Elsewhere, however, the misuse of the os has been more wanton than ient.

    Many fishermen “fin” sharks—that is, slice their fins off, then dump them bato the waterto die. In 1998, shark fins sold in the Far East for over $250 a pound. A bowl of shark finsoup retailed in Tokyo for $100. The World Wildlife Fuimated in 1994 that the numberof sharks killed each year was between 40 million and 70 million.

    As of 1995, some 37,000 industrial-sized fishing ships, plus about a million smaller boats,were betweeaking twice as many fish from the sea as they had just twenty-five yearsearlier. Trawlers are sometimes now as big as cruise ships and haul behind them s bigenough to hold a dozen jumbo jets. Some even use spotter plao locate shoals of fish fromthe air.

    It is estimated that about a quarter of every fishi hauled up tains “by-catch”—fishthat ’t be landed because they are too small or of the wrong type or caught in the wrongseason. As one observer told the Eist: “We’re still in the Dark Ages. We just drop a down and see what es up.” Perhaps as much as twenty-two millioris of suwanted fish are dumped ba the sea each year, mostly in the form of corpses. For everypound of shrimp harvested, about four pounds of fish and other marine creatures aredestroyed.

    Large areas of the North Sea floor are dragged  by beam trawlers as many as seventimes a year, a degree of disturbahat no ecosystem  withstand. At least two-thirds ofspecies in the North Sea, by maimates, are being overfished. Across the Atlantic thingsare er. Halibut once abounded in suumbers off New England that individual boatscould land twenty thousand pounds of it in a day. Now halibut is all but extinct off thenortheast coast of North America.

    Nothing, however, pares with the fate of cod. Ie fifteenth tury, the explorerJohn Cabot found cod in incredible numbers on the eastern banks of North America—shallowareas of water popular with bottom-feeding fish like cod. Some of these banks were vast.

    Gees Banks off Massachusetts is bigger thaate it abuts. The Grand Banks offNewfoundland is bigger still and for turies was always deh cod. They were thoughtto be inexhaustible. Of course they were anything but.

    By 1960, the number of spawning cod in the north Atlantic had fallen to aimated 1.6millioris. By 1990 this had sunk to 22,000 metris. In ercial terms, thecod were extinct. “Fishermen,” wrote Mark Kurlansky in his fasating history, Cod, “hadcaught them all.” The ay have lost the western Atlantic forever. In 1992, cod fishingwas stopped altogether on the Grand Banks, but as of last autumn, acc to a report inNature, stocks had not staged a eback. Kurlansky hat the fish of fish fillets and fishsticks was inally cod, but then was replaced by haddock, then by redfish, and lately byPacific pollock. These days, he notes drily, “fish” is “whatever is left.”

    Much the same  be said of many other seafoods. In the New England fisheries offRhode Island, it was once routio haul in lobsters weighing twenty pounds. Sometimes theyreached thirty pounds. Left ued, lobsters  live for decades—as much as seventyyears, it is thought—and they op growing. Nowadays few lobsters weigh more thantwo pounds on capture. “Biologists,” acc to the New York Times, “estimate that 90pert of lobsters are caught within a year after they reach the legal minimum size at aboutage six.” Despite deing catches, New England fishermen tio receive state andfederal tax iives that ence them—in some cases all but pel them—to acquirebigger boats and to harvest the seas more intensively. Today fishermen of Massachusetts arereduced to fishing the hideous hagfish, for which there is a slight market in the Far East, buteven their numbers are now falling.

    We are remarkably ignorant of the dynamics that rule life in the sea. While marine life ispoorer than it ought to be ihat have been overfished, in some naturally impoverishedwaters there is far more life than there ought to be. The <bdi>藏书网</bdi>southern os around Antarcticaproduly about 3 pert of the world’s phytoplankton—far too little, it would seem, tosupport a plex ecosystem, a does. Crab-eater seals are not a species of animal thatmost of us have heard of, but they may actually be the seost numerous large species ofanimal oh, after humans. As many as fifteen million of them may live on the pack icearound Antarctica. There are also perhaps two million Weddel seals, at least half a millionemperor penguins, and maybe as many as four million Adélie penguins. The food  isthus hopelessly top heavy, but somehow it works. Remarkably no one knows how.

    All this is a very roundabout way of making the point that we know very little about Earth’sbiggest system. But then, as we shall see in the pages remaining to us, once you start talkingabout life, there is a great deal we don’t know, not least how it got going in the first place.

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