29 THE RESTLESS APESOME

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    TIME ABOUT A million and a half years ago, some fotten genius of the hominidworld did an ued thing. He (or very possibly she) took oone and carefully used itto shape ahe result was a simple teardrop-shaped hand axe, but it was the world’sfirst piece of advaeology.

    It was so superior to existing tools that soon others were following the ior’s lead andmaking hand axes of their owually whole societies existed that seemed to do littleelse. “They made them ihousands,” says Ian Tattersall. “There are some places inAfrica where you literally ’t move without stepping on them. It’s strange because they arequite intensive objects to make. It was as if they made them for the sheer pleasure of it.”

    From a shelf in his sunny workroom Tattersall took down an enormous cast, perhaps a footand a half long a inches wide at its widest point, and ha to me. It was shapedlike a spearhead, but ohe size of a stepping-stone. As a fiberglass cast it weighed only afew ounces, but the inal, which was found in Tanzania, weighed twenty-five pounds. “Itwas pletely useless as a tool,” Tattersall said. “It would have taken two people to lift itadequately, and eve would have been exhausting to try to pound anything with it.”

    “What was it used for then?”

    Tattersall gave a genial shrug, pleased at the mystery of it. “No idea. It must have had somesymbolic importance, but we  only guess what.”

    The axes became known as Acheulean tools, after St. Acheul, a suburb of Amiens innorthern France, where the first examples were found in the eenth tury, and trastwith the older, simpler tools known as Oldowan, inally found at Olduvai Ge inTanzania. In older textbooks, Oldowan tools are usually shown as blunt, rounded, hand-sizedstones. In fact, paleoanthropologists now tend to believe that the tool part of Oldowan rockswere the pieces flaked off these larger stones, which could then be used for cutting.

    Now here’s the mystery. When early modern humans—the ones who would eventuallybee us—started to move out of Afriething over a huhousand years ago,Acheulean tools were the teology of choice. These early Homo sapiens loved theirAcheulean tools, too. They carried them vast distances. Sometimes they even took unshapedrocks with them to make into tools later on. They were, in a word, devoted to the teology.

    But although Acheulean tools have been found throughout Africa, Europe, aern aral Asia, they have almost never been found in the Far East. This is deeply puzzling.

    In the 1940s a Harvard paleontologist named Hallum Movius drew something called theMovius line, dividing the side with Acheulean tools from the ohout. The line runs in asoutheasterly dire across Europe and the Middle East to the viity of modern-dayCalcutta and Bangladesh. Beyond the Movius line, across the whole of southeast Asia andinto a, only the older, simpler Oldowan tools have been found. We know that Homosapie far beyond this point, so why would they carry an advanced and treasured stoeology to the edge of the Far East and then just abandon it?

    “That troubled me for a long time,” recalls Alan Thorne of the Australian NationalUy in berra. “The whole of modern anthropology was built round the idea thathumans came out of Afri two waves—a first wave of Homo erectus, which became JavaMan and Peking Man and the like, and a later, more advanced wave of Homo sapiens, whichdisplaced the first lot. Yet to accept that you must believe thatHomo sapiens got so far withtheir more modern teology and then, for whatever reason, gave it up. It was all verypuzzling, to say the least.”

    As it turned out, there would be a great deal else to be puzzled about, and one of the mostpuzzling findings of all would e from Thorne’s own part of the world, iback ofAustralia. In 1968, a geologist named Jim Bowler oking around on a long-dried lakebedcalled Mungo in a parched and lonely er of western New South Wales when somethingvery ued caught his eye. Stig out of a crest-shaped sand ridge of a type knownas a lue were some human bones. At the time, it was believed that humans had been inAustralia for no more than 8,000 years, but Mungo had been dry for 12,000 years. So whatwas anyone doing in su inhospitable place?

    The answer, provided by carbon dating, was that the bones’ owner had lived there whenLake Mungo was a much mreeable habitat, a dozen miles long, full of water and fish,fringed by pleasant groves of casuarina trees. To everyone’s astonishment, the bour to be 23,000 years old. Other bones found nearby were dated to as much as 60,000 years.

    This was ued to the point of seeming practically impossible. At no time sininids first arose oh has Australia not been an island. Any human beings who arrivedthere must have e by sea, in large enough o start a breeding population, aftercrossing sixty miles or more of open water without having any way of knowing that ave landfall awaited them. Having lahe Mungo people had then found their waymore than two thousand miles inland from Australia’s north coast—the presumed point ofentry—which suggests, acc to a report in the Proceedings of the National Academy ofSces, “that people may have first arrived substantially earlier than 60,000 years ago.”

    How they got there and why they came are questions that ’t be answered. Acc tomost anthropology texts, there’s no evidehat people could even speak 60,000 years ago,much less engage in the sorts of cooperative efforts necessary to build o-worthy craft andize island tis.

    “There’s just a whole lot we don’t know about the movements of people before recordedhistory,” Alan Thorold me when I met him in berra. “Do you know that wheeenth-tury anthropologists first got to Papua New Guihey found people in thehighlands of the interior, in some of the most inaccessible terrain oh, growing sweetpotatoes. Sweet potatoes are native to South America. So how did they get to Papua NewGuinea? We don’t know. Don’t have the fai idea. But what is certain is that people havebeen moving around with siderable assuredness for lohan traditionally thought, andalmost certainly sharing genes as well as information.”

    The problem, as ever, is the fossil record. “Very few parts of the world are even vaguelyameo the long-term preservation of human remains,” says Thorne, a sharp-eyed manwith a white goatee and an i but friendly manner. “If it weren’t for a few productiveareas like Hadar and Olduvai i Africa we’d knhteningly little. And when youlook elsewhere, often wedo knhteningly little. The whole of India has yielded just onea human fossil, from about 300,000 years ago. Between Iraq and Vietnam—that’s adistance of some 5,000 kilometers—there have been just two: the one in India and aNeaal in Uzbekistan.” He grinned. “That’s not a whole hell of a lot to work with. You’releft with the position that you’ve got a few productive areas for human fossils, like the GreatRift Valley in Afrid Mungo here in Australia, and very little iween. It’s notsurprising that paleontologists have trouble eg the dots.”

    The traditional theory to explain human movements—and the oill accepted by themajority of people in the field—is that humans dispersed across Eurasia in two waves. Thefirst wave sisted of Homo erectus, who left Africa remarkably quickly—almost as soon asthey emerged as a species—beginning nearly two million years ago. Over time, as they settledin different regions, these early erects further evolved into distinctive types—into Java Manand Peking Man in Asia, and Homo heidelbergensis and finally Homo neahalensis inEurope.

    Then, something over a huhousand years ago, a smarter, lither species of creature—the aors of every one of us alive today—arose on the Afri plains and began radiatingoutward in a sed wave. Wherever they went, acc to this theory, these new Homosapiens displaced their duller, less adept predecessors. Quite how they did this ha></a>s alwaysbeen a matter of disputation. No signs of slaughter have ever been found, so most authoritiesbelieve the newer hominids simply outpeted the older ohough other faay alsohave tributed. “Perhaps we gave them smallpox,” suggests Tattersall. “There’s no real wayof telling. The oainty is that we are here now and they aren’t.”

    These first modern humans are surprisingly shadowy. We know less about ourselves,curiously enough, than about almost any other line of hominids. It is odd indeed, as Tattersallnotes, “that the most ret major event in human evolution—the emergence of our ownspecies—is perhaps the most obscure of all.” Nobody  even quite agree where trulymodern humans first appear in the fossil record. Many books place their debut at about120,000 years ago in the form of remains found at the Klasies River Mouth in South Africa,but not everyone accepts that these were fully modern people. Tattersall and Schwartzmaintain that “whether any or all of them actually represent our species still awaits definitiveclarification.”

    The first undisputed appearance of Homo sapiens is in the eastererranean, aroundmodern-day Israel, where they begin to show up about 100,000 years ago—but evehey are described (by Trinkaus and Shipman) as “odd, difficult-to-classify and poorlyknown.” Neaals were already well established in the region and had a type of tool kitknown as Mousterian, which the modern humans evidently found worthy enough to borrow.

    No Neaal remains have ever been found in north Africa, but their tool kits turn up allover the place. Somebody must have takehere: modern humans are the onlydidate. It is also known that Neaals and modern humans coexisted in some fashionfor tens of thousands of years in the Middle East. “We don’t know if they time-shared thesame space or actually lived side by side,” Tattersall says, but the moderns tinued happilyto use Neaal tools—hardly ving evidence of overwhelming superiority. No lesscuriously, Acheulean tools are found in the Middle East well over a million years ago, butscarcely exist in Europe until just 300,000 years ago. Again, why people who had theteology didn’t take the tools with them is a mystery.

    For a long time, it was believed that the agnons, as modern humans in Europebecame known, drove the Neaals before them as they advanced across the ti,eventually f them to its western margins, where essentially they had no choice but tofall in the sea o extinct. In fact, it is now known that agnons were in the far west ofEurope at about the same time they were also ing in from the east. “Europe rettyempty pla those days,” Tattersall says. “They may not have entered each other allthat often, even with all their ings and goings.” One curiosity of the agnons’ arrivalis that it came at a time known to paleoclimatology as the Boutellier interval, when Europelunging from a period of relative mildness into yet another long spell of punishing cold.

    Whatever it was that drew them to Europe, it wasn’t the glorious weather.

    In any case, the idea that Neaals crumpled in the face of petition from newlyarrived agnons strains against the evide least a little. Neaals were nothing ifnot tough. For tens of thousands of years they lived through ditions that no modern humanoutside a few polar stists and explorers has experienced. During the worst of the ice ages,blizzards with hurrie-force winds were on. Temperatures routinely fell to 50 degreesbelow zero Fahre. Polar bears padded across the snowy vales of southern England.

    Neaals naturally retreated from the worst of it, but even so they will have experiencedweather that was at least as bad as a modern Siberian wihey suffered, to be sure—aNeaal who lived much past thirty was lucky indeed—but as a species they weremagnifitly resilient and practically iructible. They survived for at least a huhousand years, and perhaps twice that, over aretg from Gibraltar to Uzbekistan,which is a pretty successful run for any species of being.

    Quite who they were and what they were like remain matters of disagreement anduainty. Right up until the middle of the tweh tury the accepted anthropologicalview of the Neaal was that he was dim, stooped, shuffling, and simian—thequintessential caveman. It was only a painful act that prodded stists to residerthis view. In 1947, while doing fieldwork in the Sahara, a Franco-Algerian paleontologistnamed Camille Aramb te from the midday sun uhe wing of his lightairplane. As he sat there, a tire burst from the heat, and the plaipped suddenly, striking hima painful blow on the upper body. Later in Paris he went for an X-ray of his neck, and noticedthat his owebrae were aligly like those of the stooped and hulking Neaal.

    Either he hysiologically primitive or Neaal’s posture had been misdescribed. Infact, it was the latter. Neaal vertebrae were not simian at all. It ged utterly how weviewed Neaals—but only some of the time, it appears.

    It is still only held that Neaals lacked the intelligence or fiber to pete onequal terms with the ti’s slender and more cerebrally nimble newers, Homosapiens. Here is a typical ent from a ret book: “Modern humaralized thisadvahe Neaal’s siderably heartier physique] with better clothing, better firesaer shelter; meanwhile the Neaals were stuck with an oversize body that requiredmore food to sustain.” In other words, the very factors that had allowed them to survivesuccessfully for a huhousand years suddenly became an insuperable handicap.

    Above all the issue that is almost never addressed is that Neaals had brains that weresignifitly larger than those of modern people—1.8 liters for Neaals versus 1.4 formodern people, acc to one calculation. This is more than the differeweenmodern Homo sapiens and late Homo erectus , a species we are happy tard as barelyhuman. The argument put forward is that although our brains were smaller, they weresomehow more effit. I believe I speak the truth when I observe that nowhere else inhuman evolution is su argument made.

    So why then, you may well ask, if the Neaals were so stout and adaptable andcerebrally well endowed, are they no longer with us? One possible (but much disputed)answer is that perhaps they are. Alan Thorne is one of the leading propos of an alternativetheory, known as the multiregional hypothesis, which holds that human evolution has beentinuous—that just as australopithees evolved into Homo habilis and Homoheidelbergensis became over time Homo neahalensis, so modernHomo sapiens simplyemerged from more a Homo forms.Homo erectus is, on this view, not a separate speciesbut just a transitional phase. Thus modern ese are desded from a Homo erectusforebears in a, modern Europeans from a European Homo erectus, and so on.

    “Except that for me there are no Homo erectus,” says Thorne. “I think it’s a term which hasoutlived its usefulness. For me, Homo erectus is simply an earlier part of us. I believe onlyone species of humans has ever left Africa, and that species isHomo sapiens.”

    Oppos of the multiregional theory reject it, in the first instance, on the grounds that itrequires an improbable amount of parallel evolution by hominids throughout the Old World—in Africa, a, Europe, the most distant islands of Indonesia, wherever they appeared. Somealso believe that multiregionalism ences a racist view that anthropology took a very longtime to rid itself of. In the early 1960s, a famous anthropologist named Carleton  of theUy of Pennsylvania suggested that some modern races have different sources in, implying that some of us e from more superior stock than others. This hearkenedbafortably to earlier beliefs that some modern races such as the Afri “Bushmen”

    (properly the Kalahari San) and Australian Abines were more primitive than others.

    Whatever ay personally have felt, the implication for many people was that someraces are ily more advanced, and that some humans could essentially stitutedifferent species. The view, so instinctively offensive noidely popularized in manyrespectable places until fairly ret times. I have before me a popular book published byTime-Life Publications in 1961 called The Epian based on a series of articles in Lifemagazine. In it you  find suents as “Rhodesian man . . . lived as retly as25,000 years ago and may have been an aor of the Afriegroes. His brain size wasclose to that of Homo sapiens.” In other words black Afris were retly desded fromcreatures that were only “close” to Homo sapiens.

    Thorne emphatically (and I believe sincerely) dismisses the idea that his theory is in anymeasure racist and ats for the uniformity of human evolution by suggesting that therewas a lot of movement bad forth between cultures and regions. “There’s no reason tosuppose that people only went in one dire,” he says. “People were moving all over theplace, and where they met they almost certainly shared geic material throughinterbreeding. New arrivals didn’t replace the indigenous populations, they joihem. Theybecame them.” He likens the situation to when explorers like Coellan enteredremote peoples for the first time. “They weren’t meetings of different species, but of the samespecies with some physical differences.”

    What you actually see in the fossil record, Thorne insists, is a smooth, tinuoustransition. “There’s a famous skull from Petralona in Greece, dating from about 300,000 yearsago, that has been a matter of tention among traditionalists because it seems in some waysHomo erectus but in other ways Homo sapiens. Well, what we say is that this is just what youwould expect to find in species that were evolving rather than being displaced.”

    Ohing that would help to resolve matters would be evidence of interbreeding, but that isnot at all easy to prove, or disprove, from fossils. In 1999, archeologists in Pal found theskeleton of a child about four years old that died 24,500 years ago. The skeleton was modernoverall, but with certain archaic, possibly Neaal, characteristics: unusually sturdy legboeeth bearing a distinctive “s<tt>..t>hoveling” pattern, and (though not everyone agrees on it)an iion at the back of the skull called a suprainiac fossa, a feature exclusive toNeaals. Erik Trinkaus of Washington Uy in St. Louis, the leading authority onNeaals, annouhe child to be a hybrid: proof that modern humans and Neaalsinterbred. Others, however, were troubled that the Neaal and moderures weren’tmore blended. As one critic put it: “If you look at a mule, you don’t have the front endlooking like a donkey and the bad looking like a horse.”

    Ian Tattersall declared it to be nothing more than “a ky modern child.” He accepts thatthere may well have been some “hanky-panky” between Neaals and moderns, butdoesn’t believe it could have resulted in reproductively successful offspring.

    1“I don’t knowof any twanisms from any realm of biology that are that different and still in the samespecies,” he says.

    With the fossil record so unhelpful, stists have turned increasingly to geic studies,in particular the part known as mitodrial DNA. Mitodrial DNA was only discoveredin 1964, but by the 1980s some ingenious souls at the Uy of California at Berkeley hadrealized that it has two features that lend it a particular venience as a kind of molecularclock: it is passed on only through the female line, so it doesn’t bee scrambled withpaternal DNA with eaew geion, and it mutates about twenty times faster than normalnuclear DNA, makin<cite>?9９ｌｉｂ?</cite>g it easier to deted follow geic patterns over time. By trag therates of mutation they could work out the geic history aionships of whole groups ofpeople.

    In 1987, the Berkeley team, led by the late Allan Wilson, did an analysis of mitodrialDNA from 147 individuals and declared that the rise of anatomically modern humansoccurred in Africa within the last 140,000 years and that “all present-day humans aredesded from that population.” It was a serious blow to the multiregionalists. But thenpeople began to look a little more closely at the data. One of the most extraordinary points—almost too extraordinary to credit really—was that the “Afris” used iudy wereactually Afri-Ameris, whose genes had obviously been subjected to siderablemediation in the past few hundred years. Doubts also soon emerged about the assumed ratesof mutations.

    By 1992, the study was largely discredited. But the teiques of geialysistio be refined, and in 1997 stists from the Uy of Munich maoextrad analyze some DNA from the arm bone of the inal Neaal man, and thistime the evideood up. The Munich study found that the Neaal DNA was unlike anyDNA found oh now, strongly indig that there was iioweenNeaals and modern humans. Now this really was a blow to multiregionalism.

    1One possibility is that Neaals and agnons had different numbers of osomes, a plicationthat only arises when species that are close but not quite identical join. In the equine world, forexample, horses have 64 osomes and donkeys 62. Mate the two and you get an offspring with areproductively useless number of osomes, 63. You have, in short, a sterile mule.

    Then in late 2000 Nature and other publicatioed on a Swedish study of themitodrial DNA of fifty-three people, which suggested that all modern humans emergedfrom Africa within the past 100,000 years and came from a breeding stock of no more than10,000 individuals. Soon afterward, Erider, director of the WhiteheadInstitute/Massachusetts Institute of Teology ter fenome Research, annouhatmodern Europeans, and perhaps people farther afield, are desded from “no more than afew hundred Afris who left their homeland as retly as 25,000 years ago.”

    As we have noted elsewhere in the book, modern human beings show remarkably littlegeic variability—“there’s more diversity in one social group of fifty-five chimps than iire human population,” as ohority has put it—and this would explain why.

    Because we are retly desded from a small founding population, there hasn’t been timeenough or people enough to provide a source of great variability. It seemed a pretty severeblow to multiregionalism. “After this,” a Penn State academic told the Washington Post,“people won’t be too ed about the multiregional theory, which has very littleevidence.”

    But all of this overlooked the more or less infinite capacity for surprise offered by thea Mungo people of western New South Wales. In early 2001, Thorne and his colleaguesat the Australian National Uy reported that they had recovered DNA from the oldest ofthe Mungo spes—now dated at 62,000 years—and that this DNA proved to be“geically distinct.”

    The Mungo Man, acc to these findings, was anatomically modern—just like you a carried ainct geieage. His mitodrial DNA is no longer found inliving humans, as it should be if, like all other modern people, he was desded from peoplewho left Afri the ret past.

    “It turned everything upside down again,” says Thorh undisguised delight.

    Then other even more curious anomalies began to turn up. Rosalind Harding, a populatioicist at the Institute of Biological Anthropology in Oxford, while studyiaglobingenes in modern people, found two variants that are ong Asians and theindigenous people of Australia, but hardly exist in Africa. The variant genes, she is certain,arose more than 200,000 years ago not in Africa, but i Asia—long before modern Homosapiens reached the region. The only way to at for them is to say that aors ofpeople now living in Asia included archaiinids—Java Man and the like. Iingly,this same variahe Java Man gene, so to speak—turns up in modern populations inOxfordshire.

    fused, I went to see Harding at the institute, whihabits an old brick villa onBanbury Road in Oxford, in more or less the neighborhood where Bill to hisstudent days. Harding is a small and chirpy Australian, from Brisbane inally, with the rareknack for being amused and ear at the same time.

    “Don’t know,” she said at once, grinning, when I asked her how people in Oxfordshireharbored sequences of betaglobin that shouldn’t be there. “On the whole,” she went on moresomberly, “the geic record supports the out-of-Africa hypothesis. But then you find theseanomalous clusters, which most geicists prefer not to talk about. There’s huge amounts ofinformation that would be available to us if only we could uand it, but we don’t yet.

    We’ve barely begun.” She refused to be drawn out on what the existence of Asian-ingenes in Oxfordshire tells us other than that the situation is clearly plicated. “All we say at this stage is that it is very untidy and we don’t really know why.”

    At the time of our meeting, in early 2002, another Oxford stist named Bryan Sykes hadjust produced a popular book called The Seven Daughters of Eve in which, using studies ofmitodrial DNA, he had claimed to be able to traearly all living Europeans back to afounding population of just seven women—the daughters of Eve of the title—who livedbetween 10,000 and 45,000 years ago iime known to sce as the Paleolithic. To eachof these women Sykes had given a name—Ursula, Xenia, Jasmine, and so on—and eveailed personal history. (“Ursula was her mother’s sed child. The first had been taken bya leopard when he was only two. . . .”)When I asked Harding about the book, she smiled broadly but carefully, as if not quitecertaio go with her answer. “Well, I suppose you must give him some credit forhelping to popularize a difficult subject,” she said and paused thoughtfully. “And thereremains the remote possibility that he’s right.” She laughed, the on more ily:

    “Data from any single gene ot really tell you anything so definitive. If you follow themitodrial DNA backwards, it will take you to a certain place—to an Ursula or Tara orwhatever. But if you take any other bit of DNA, any ge all, and traceit back, it will takeyou someplace else altogether.”

    It was a little, I gathered, like following a road random<tt>９9ｌib.t>ly out of London and finding thateventually it ends at John O’Groats, and cluding from this that anyone in London musttherefore have e from the north of Scotland. They might have e from there, of course,but equally they could have arrived from any of hundreds of other places. In this sense,acc t, every gene is a different highway, and we have only barely begun tomap the routes. “No single gene is ever going to tell you the whole story,” she said.

    So geic studies aren’t to be trusted?

    “Oh you  trust the studies well enough, generally speaking. What you ’t trust are thesweeping clusions that people often attach to them.”

    She thinks out-of-Africa is “probably 95 pert correct,” but adds: “I think both sides havedone a bit of a disservice to sce by insisting that it must be ohing or the other. Thingsare likely to turn out to be not shtforward as either camp would have you believe. Theevidence is clearly starting to suggest that there were multiple migrations and dispersals indifferent parts of the woing in all kinds of dires and generally mixing up the genepool. That’s never going to be easy to sort out.”

    Just at this time, there were also a number of reports questioning the reliability of claimsing the recovery of very a DNA. An academic writing in Nature had noted hoaleontologist, asked by a colleague whether he thought an old skull was varnished or not,had licked its top and annouhat it was. “In the process,” he Nature article, “largeamounts of modern human DNA would have been transferred to the skull,” rendering ituseless for future study. I asked Harding about this. “Oh, it would almost certainly have beeninated already,” she said. “Just handling a bone will i. Breathing on itwill i. Most of the water in our labs will i. We are all swimming infn DNA. In order to get a reliably  spe you have to excavate it in sterileditions and do the tests on it at the s<q>?</q>ite. It is the trickiest thing in the world not toinate a spe.”

    So should such claims be treated dubiously? I asked.

    Harding nodded solemnly. “Very,” she said.

    If you wish to uand at once why we know as little as we do about human ins, Ihave the place for you. It is to be found a little beyond the edge of the blue Ngong Hills inKenya, to the south a of Nairobi. Drive out of the city on the main highway toUganda, and there es a moment of startling glory when the ground falls away and you arepresented with a hang glider’s view of boundless, pale green Afri plain.

    This is the Great Rift Valley, which arcs across three thousand miles of east Africa,marking the teic rupture that is setting Africa adrift from Asia. Here, perhaps forty milesout of Nairobi, along the baking valley floor, is an a site called esailie, whicestood beside a large and pleasant lake. In 1919, long after the lake had vanished, a geologistnamed J. W. Gregory was scouting the area for mineral prospects when he came across astretch of open ground littered with anomalous dark stohat had clearly been shaped byhuman hand. He had found one of the great sites of Acheulean tool manufacture that IanTattersall had told me about.

    Uedly iumn of 2002 I found myself a visitor to this extraordinary site. Iwas in Kenya for another purpose altogether, visiting some projects run by the charity CAREIional, but my hosts, knowing of my i in humans for the present volume, hadied a visit to esailie into the schedule.

    After its discovery by Gregory, esailie lay undisturbed for over two decades beforethe famed husband-and-wife team of Louis and Mary Leakey began an excavation that isn’tpleted yet. What the Leakeys found was a site stretg to ten acres or so, where toolswere made in incalculable numbers fhly a million years, from about 1.2 million yearsago to 200,000 years ago. Today the tool beds are sheltered from the worst of the elemeh large tios and fenced off with chi wire to disce opportunisticsging by visitors, but otherwise the tools are left just where their creators dropped themand where the Leakeys found them.

    Jillani Ngalli, a keen young man from the Kenyan National Museum who had beendispatched to act as guide, told me that the quartz and obsidian rocks from which the axeswere made were never found on the valley floor. “They had to carry the stones from there,” hesaid, nodding at a pair of mountains in the hazy middle distance, in opposite dires fromthe site: esailie and Ol Esakut. Each was about ten kilometers, or six miles, away—along way to carry an armload of stone.

    Why the early esailie people went to such trouble we  only guess, of course. Notonly did they lug hefty stones siderable distao the lakeside, but, perhaps even moreremarkably, they then ahe site. The Leakeys’ excavations revealed that there wereareas where axes were fashioned and others where blunt axes were brought to be resharpened.

    esailie was, in short, a kind of factory; ohat stayed in business for a million years.

    Various replications have shown that the axes were tricky and labor-intensive objects tomake—even with practice, an axe would take hours to fashion—a, curiously, they werenot particularly good for cutting or chopping or scraping or any of the other tasks to whichthey were presumably put. So we are left with the position that for a million years—far, farlohan our own species has even been ience, much less engaged in tinuouscooperative efforts—early people came in siderable o this particular site to makeextravagantly large numbers of tools that appear to have been rather curiously pointless.

    And who were these people? We have no idea actually. We assume they were Homoerectus because there are no other known didates, which means that at their peak—theirpeak —the esailie workers would have had the brains of a modern infant. But there is nophysical eviden which to base a clusioe over sixty years of searg, nohuman bone has ever been found in or around the viity of esailie. However muchtime they spent there shaping rocks, it appears they went elsewhere to die.

    “It’s all a mystery,” Jillani Ngalli told me, beaming happily.

    The esailie people disappeared from the se about 200,000 years ago when the lakedried up and the Rift Valley started to bee the hot and challenging place it is today. Butby this time their days as a species were already numbered. The world was about to get itsfirst real master race, Homo sapiens . Things would never be the same again.

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