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e it seems in some ways homo 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。鈥�
one thing 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 portugal found theskeleton of a child about four years old that died 24；500 years ago。 the skeleton was modernoverall； but with certain archaic； possibly neandertal； characteristics： unusually sturdy legbones； teeth bearing a distinctive 鈥渟hoveling鈥潯attern； and （though not everyone agrees on it）an indentation at the back of the skull called a suprainiac fossa； a feature exclusive toneandertals。 erik trinkaus of washington university in st。 louis； the leading authority onneandertals； announced the child to be a hybrid： proof that modern humans and neandertalsinterbred。 others； however； were troubled that the neandertal and modern features weren鈥檛more blended。 as one critic put it： 鈥渋f you look at a mule； you don鈥檛 have the front endlooking like a donkey and the back end looking like a horse。鈥�
ian tattersall declared it to be nothing more than 鈥渁 chunky modern child。鈥潯e accepts thatthere may well have been some 鈥渉anky…panky鈥潯etween neandertals and moderns； butdoesn鈥檛 believe it could have resulted in reproductively successful offspring。
1鈥渋 don鈥檛 knowof any two organisms from any realm of biology that are that different and still in the samespecies；鈥潯e says。
with the fossil record so unhelpful； scientists have turned increasingly to genetic studies；in particular the part known as mitochondrial dna。 mitochondrial dna was only discoveredin 1964； but by the 1980s some ingenious souls at the university of california at berkeley hadrealized that it has two features that lend it a particular convenience as a kind of molecularclock： it is passed on only through the female line； so it doesn鈥檛 bee scrambled withpaternal dna with each new generation； and it mutates about twenty times faster than normalnuclear dna； making it easier to detect and follow genetic patterns over time。 by tracking therates of mutation they could work out the genetic history and relationships of whole groups ofpeople。
in 1987； the berkeley team； led by the late allan wilson； did an analysis of mitochondrialdna from 147 individuals and declared that the rise of anatomically modern humansoccurred in africa within the last 140；000 years and that 鈥渁ll present…day humans aredescended from that population。鈥潯t 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鈥攁lmost too extraordinary to credit really鈥攚as that the 鈥渁fricans鈥潯sed in the study wereactually african…americans； whose genes had obviously been subjected to considerablemediation in the past few hundred years。 doubts also soon emerged about the assumed ratesof mutations。
by 1992； the study was largely discredited。 but the techniques of genetic analysiscontinued to be refined； and in 1997 scientists from the university of munich managed toextract and analyze some dna from the arm bone of the original neandertal man； and thistime the evidence stood up。 the munich study found that the neandertal dna was unlike anydna found on earth now； strongly indicating that there was no genetic connection betweenneandertals and modern humans。 now this really was a blow to multiregionalism。
1one possibility is that neandertals and cro…magnons had different numbers of chromosomes； a plicationthat monly arises when species that are close but not quite identical conjoin。 in the equine world； forexample； horses have 64 chromosomes and donkeys 62。 mate the two and you get an offspring with areproductively useless number of chromosomes； 63。 you have； in short； a sterile mule。
then in late 2000 nature and other publications reported on a swedish study of themitochondrial 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； eric lander； director of the whiteheadinstitute/massachusetts institute of technology center for genome research； announced thatmodern europeans； and perhaps people farther afield； are descended from 鈥渘o more than afew hundred africans who left their homeland as recently as 25；000 years ago。鈥�
as we have noted elsewhere in the book； modern human beings show remarkably littlegenetic variability鈥斺�渢here鈥檚 more diversity in one social group of fifty…five chimps than inthe entire human population；鈥潯s one authority has put it鈥攁nd this would explain why。
because we are recently descended from a small founding population； there hasn鈥檛 been timeenough or people enough to provide a source of great variability。 it seemed a pretty severeblow to multiregionalism。 鈥渁fter this；鈥潯 penn state academic told the washington post；鈥減eople won鈥檛 be too concerned about the multiregional theory； which has very littleevidence。鈥�
but all of this overlooked the more or less infinite capacity for surprise offered by theancient mungo people of western new south wales。 in early 2001； thorne and his colleaguesat the australian national university reported that they had recovered dna from the oldest ofthe mungo specimens鈥攏ow dated at 62；000 years鈥攁nd that this dna proved to be鈥済enetically distinct。鈥�
the mungo man； according to these findings； was anatomically modern鈥攋ust like you andme鈥攂ut carried an extinct genetic lineage。 his mitochondrial dna is no longer found inliving humans； as it should be if； like all other modern people； he was descended from peoplewho left africa in the recent past。
鈥渋t turned everything upside down again；鈥潯ays thorne with undisguised delight。
then other even more curious anomalies began to turn up。 rosalind harding； a populationgeneticist at the institute of biological anthropology in oxford； while studying betaglobingenes in modern people； found two variants that are mon among 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 in east asia鈥攍ong before modern homosapiens reached the region。 the only way to account for them is to say that ancestors ofpeople now living in asia included archaic hominids鈥攋ava man and the like。 interestingly；this same variant gene鈥攖he java man gene； so to speak鈥攖urns up in modern populations inoxfordshire。
confused； i went to see harding at the institute； which inhabits an old brick villa onbanbury road in oxford； in more or less the neighborhood where bill clinton spent hisstudent days。 harding is a small and chirpy australian； from brisbane originally； with the rareknack for being amused and earnest at the same time。
鈥渄on鈥檛 know；鈥潯he said at once； grinning； when i asked her how people in oxfordshireharbored sequences of betaglobin that shouldn鈥檛 be there。 鈥渙n the whole；鈥潯he went on moresomberly； 鈥渢he genetic record supports the out…of…africa hypothesis。 but then you find theseanomalous clusters； which most geneticists prefer not to talk about。 there鈥檚 huge amounts ofinformation that would be available to us if only we could understand it； but we don鈥檛 yet。
we鈥檝e barely begun。鈥潯he refused to be drawn out on what the existence of asian…origin genes in oxfordshire tells us other than that the situation is clearly plicated。 鈥渁ll we cansay at this stage is that it is very untidy and we don鈥檛 really know why。鈥�
at the time of our meeting； in early 2002； another oxford scientist named bryan sykes hadjust produced a popular book called the seven daughters of eve in which； using studies ofmitochondrial dna； he had claimed to be able to trace nearly all living europeans back to afounding population of just seven women鈥攖he daughters of eve of the title鈥攚ho livedbetween 10；000 and 45；000 years ago in the time known to science as the paleolithic。 to eachof these women sykes had given a name鈥攗rsula； xenia； jasmine； and so on鈥攁nd even adetailed personal history。 （鈥渦rsula was her mother鈥檚 second child。 the first had been taken bya leopard when he was only two。 。 。 。鈥潱﹚hen i asked harding about the book； she smiled broadly but carefully； as if not quitecertain where to go with her answer。 鈥渨ell； i suppose you must give him some credit forhelping to popularize a difficult subject；鈥潯he said and paused thoughtfully。 鈥渁nd thereremains the remote possibility that he鈥檚 right。鈥潯he laughed； then went on more intently：
鈥渄ata from any single gene cannot really tell you anything so definitive。 if you follow themitochondrial dna backwards； it will take you to a certain place鈥攖o an ursula or tara orwhatever。 but if you take any other bit of dna； any gene at all； and traceit back； it will takeyou someplace else altogether。鈥�
it was a little； i gathered； like following a road randomly out of london and finding thateventually it ends at john o鈥檊roats； and concluding from this that anyone in london musttherefore