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homo habilis consists of even less： just two partial skeletons and a number of isolated limbbones。 something as short…lived as our own civilization would almost certainly not be knownfrom the fossil record at all。
“in europe；” tattersall offers by way of illustration； “you’ve got hominid skulls in georgiadated to about 1。7 million years ago； but then you have a gap of almost a million years beforethe next remains turn up in spain； right on the other side of the continent； and then you’ve gotanother 300；000…year gap before you get a homo heidelbergensis in germany—and none ofthem looks terribly much like any of the others。” he smiled。 “it’s from these kinds offragmentary pieces that you’re trying to work out the histories of entire species。 it’s quite atall order。 we really have very little idea of the relationships between many ancient species—which led to us and which were evolutionary dead ends。 some probably don’t deserve to beregarded as separate species at all。”
it is the patchiness of the record that makes each new find look so sudden and distinct fromall the others。 if we had tens of thousands of skeletons distributed at regular intervals throughthe historical record； there would be appreciably more degrees of shading。 whole new speciesdon’t emerge instantaneously； as the fossil record implies； but gradually out of other； existingspecies。 the closer you go back to a point of divergence； the closer the similarities are； so thatit bees exceedingly difficult； and sometimes impossible； to distinguish a late homoerectus from an early homo sapiens； since it is likely to be both and neither。 similardisagreements can often arise over questions of identification from fragmentary remains—deciding； for instance； whether a particular bone represents a female australopithecus boiseior a male homo habilis。
with so little to be certain about； scientists often have to make assumptions based on otherobjects found nearby； and these may be little more than valiant guesses。 as alan walker andpat shipman have drily observed； if you correlate tool discovery with the species of creaturemost often found nearby； you would have to conclude that early hand tools were mostly madeby antelopes。
perhaps nothing better typifies the confusion than the fragmentary bundle of contradictionsthat was homo habilis。 simply put； habilis bones make no sense。 when arranged in sequence；they show males and females evolving at different rates and in different directions—the malesbeing less apelike and more human with time； while females from the same period appearto be moving away from humanness toward greater apeness。 some authorities don’t believehabilis is a valid category at all。 tattersall and his colleague jeffrey schwartz dismiss it as amere “wastebasket species”—one into which unrelated fossils “could be conveniently swept。”
even those who see habilis as an independent species don’t agree on whether it is of the samegenus as us or is from a side branch that never came to anything。
finally； but perhaps above all； human nature is a factor in all this。 scientists have a naturaltendency to interpret finds in the way that most flatters their stature。 it is a rare paleontologistindeed who announces that he has found a cache of bones but that they are nothing to getexcited about。 or as john reader understatedly observes in the book missing links； “it isremarkable how often the first interpretations of new evidence have confirmed thepreconceptions of its discoverer。”
all this leaves ample room for arguments； of course； and nobody likes to argue more thanpaleoanthropologists。 “and of all the disciplines in science； paleoanthropology boasts perhapsthe largest share of egos；” say the authors of the recent java man —a book； it may be noted；that itself devotes long； wonderfully unselfconscious passages to attacks on the inadequaciesof others； in particular the authors’ former close colleague donald johanson。 here is a smallsampling：
in our years of collaboration at the institute he ＇johanson＇ developed a well…deserved； if unfortunate； reputation for unpredictable and high…decibel personalverbal assaults； sometimes acpanied by the tossing around of books orwhatever else came conveniently to hand。
so； bearing in mind that there is little you can say about human prehistory that won’t bedisputed by someone somewhere； other than that we most certainly had one； what we thinkwe know about who we are and where we e from is roughly this：
for the first 99。99999 percent of our history as organisms； we were in the same ancestralline as chimpanzees。 virtually nothing is known about the prehistory of chimpanzees； butwhatever they were； we were。 then about seven million years ago something major happened。
a group of new beings emerged from the tropical forests of africa and began to move abouton the open savanna。
these were the australopithecines； and for the next five million years they would be theworld’s dominant hominid species。 （austral is from the latin for “southern” and has noconnection in this context to australia。） australopithecines came in several varieties； someslender and gracile； like raymond dart’s taung child； others more sturdy and robust； but allwere capable of walking upright。 some of these species existed for well over a million years；others for a more modest few hundred thousand； but it is worth bearing in mind that even theleast successful had histories many times longer than we have yet achieved。
the most famous hominid remains in the world are those of a 3。18…million…year…oldaustralopithecine found at hadar in ethiopia in 1974 by a team led by donald johanson。
formally known as a。l。 （for “afar locality”） 288–1； the skeleton became more familiarlyknown as lucy； after the beatles song “lucy in the sky with diamonds。” johanson has neverdoubted her importance。 “she is our earliest ancestor； the missing link between ape andhuman；” he has said。
lucy was tiny—just three and a half feet tall。 she could walk； though how well is a matterof some dispute。 she was evidently a good climber； too。 much else is unknown。 her skull wasalmost entirely missing； so little could be said with confidence about her brain size； thoughskull fragments suggested it was small。 most books describe lucy’s skeleton as being 40percent plete； though some put it closer to half； and one produced by the americanmuseum of natural history describes lucy as two…thirds plete。 the bbc television series ape man actually called it “a plete skeleton；” even while showing that it was anythingbut。
a human body has 206 bones； but many of these are repeated。 if you have the left femurfrom a specimen； you don’t need the right to know its dimensions。 strip out all the redundantbones； and the total you are left with is 120—what is called a half skeleton。 even by this fairlyacmodating standard； and even counting the slightest fragment as a full bone； lucyconstituted only 28 percent of a half skeleton （and only about 20 percent of a full one）。
in the wisdom of the bones； alan walker recounts how he once asked johanson how hehad e up with a figure of 40 percent。 johanson breezily replied that he had discounted the106 bone