Out of Africa and Into Asia
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NEWS AND VIEWS PALAEOANTHROPOLOGY------------------------------------------------------------- ported by analysis of tooth enamel from Out of Africa and into Asia the sediments, using electron spin reso nance, which gives a minimum age of 0.75 Bernard Wood and Alan Turner ± 0.09 Myr based on an early uranium uptake model. It could be argued that the FEw doubt that Africa was the birthplace discovered. Despite being allocated to a normal magnetic event associated with of the hominid lineage, but there is new genus and species, their affinities the material is therefore likely to be no equivalent consensus about when with the hominids from Trinil, and with Jaramillo, but the associated mammalian hominids first moved out of that continent. similar material that was subsequently fauna is really too archaic and points Despite the announcement of early recovered at Sangiran, also in Indonesia, instead to the earlier Olduvai event. Of dates for a juvenile Homo erectus from was evident, and the Chinese remains particular interest here is the presence of Indonesia1, the circumstances surrounding have also been subsumed within H. Nestoritherium, a genus of the family Chal the recovery of many of the fossil hominids erectus. There have been sporadic icotheriidae, an extinct, bizarre, claw from the island will always hinder attempts attempts to demonstrate both that the hoofed member of the Perissodactyla, to date them. Thus the excavation of hominid remains from the Indonesian today represented by tapirs, rhinos and hominid remains, in combination with sites are from more than one species4•5, horses. crudely fashioned artefacts in what are and that they include specimens that The lithic items identified as primitive claimed to be earliest Pleistocene deposits should be allocated toAustralopithecus6 or stone tools do seem to be exotic, and they at Longgupo Cave in central China Paranthropus7, and thus to an earlier, are notably larger than the rest of the sed (Huang and co-workers, page 275 of this more primitive phase of hominid evolu iments. They look as much like stone tools issue2), is of major importance. Most tion. But none of these claims has sur as anything of this age ever does, and they notably, the remains lend support to the vived close scrutinl. Likewise, until fall into the category of items in finer idea3 that representatives of the hominid recently there has been little compelling sediment deposits that, as Gamble9 has lineage were established in mainland evidence to suggest that any of the Asian pointed out, tend to categorize genuine Asia as early as about 1.9 million years hominid sites were yielding hominids archaeological assemblages as opposed to (Myr) ago. more than one million years old3. naturally bashed stones. Moreover, the Africa has been the focus for research The importance of the material from uneroded state of the bone in clay facies into human evolutionary history for the Longgupo Cave is twofold. Not only does channels is consistent with primary depo past three decades, but it was not always it support an early date for the hominid sition rather than intrusive burial. But we thus. A century ago, space in the corre occupation of Asia, but the morphological are unlikely to be dealing with a site of spondence columns of Nature was regular details of the admittedly fragmentary fos hominid occupation. The giant hyaena, ly claimed to debate the significance of sil evidence also mean that it may repre Pachycrocuta, is a perfectly plausible agent the finds Eugene Dubois had made, sent not H. erectus but a more primitive of accumulation w (it is less likely that the beginning in 1891, at Trinil in Indonesia. species akin to H. ergaster, thus far known sabre-toothed Homotherium did much Although initially allocated to Pithecan only from Africa. bone destroying). thropus erectus, the species distinction of Of course, dating the material is crucial The authors draw attention to the pres the Trinil hominid has survived but the to the argument. Longgupo Cave has ence of Gigantopithecus, a large, gorilla genus has long since been sunk into several lines of evidence, none of them like and presumably herbivorous primate, Homo. contradictory. Palaeomagnetic stratigra in the same level as the hominid fossils, Two decades later, excavations were phy shows a reversed polarity for most of and stress that this is the third such co instigated by the Canadian anatomist the sediments, with the hominid fossils occurrence at Asian localities over a time Davidson Black in the cave deposits at and lithic items associated with the lower span of some 1 Myr. Such co-occurrences Choukoutien, now called Zhoukoudian, of two normal events and therefore are always intriguing, but the evidence of and the first of the series of remains of referred to the Olduvai magnetic event. hyaena activity reduces the likelihood that what became known as 'Peking Man' was The magnetic evidence is broadly sup- Gigantopithecus was prey to the more Australopithecus goes west As discussed in the main article, on some 3-3.5 Myr old, from Chad. The clearly australopithecine in grade. It page 275 of this issue Huang et a/. known range of that genus is thus is closest in morphology to Australo report evidence that bears upon the extended westward by 2,000 km or so. pithecus afarensis, but may turn out to expansion of the range of hominids Determining the range of an extinct be a new species; given its location, beyond Africa. But how well do we species is particularly tricky. What this would not be surprising. In the understand their distribution within should the null hypothesis be? If the Pliocene, habitats similar to those that continent? Early hominid sites in starting point is that the range is deter indicated by the fauna associated with Africa are concentrated in two regions: mined by the location of fossil discover the Chad discovery extended from the East Africa, where they are centred on ies, how does one accommodate the Atlantic Ocean to the Cape. There is the Gregory Rift Valley, and southern maxim that 'absence of evidence is not no reason to think that australo Africa, where fossil evidence has come evidence of absence'? Even if suitable pithecines did not use that range to from caves located in the high veldt. fossil sites exist, low population density the full. B. W. Discoveries in Malawi 1 have helped to and the vagaries of preservation will 2 bridge the gap between the two areas , result in the representation of some 1. Schrenk, F., Bromage, T. G., Betzler, C. G. & Ring, U. but were the early hominids as restrict species being very patchy. The Mio Nature 365, 833-836 (1993). 2. Wood, B. Nature 365, 789-790 (1993). 4 ed in their range as the distribution of Piiocene hyaenids are a good example , 3. Brunet, M. eta/. Nature 378, 273-275 (1995). these sites suggests? and Agriotherium, a fossil bear, is only 4. Werdelin, L.. Turner, A. & Solounias, N. Zoo/. J. Linn. Soc. 111, 197-217 (1994). Apparently not, for on page 273 known from two sites in AfricaS, but 5. Howell, F. C. in Neogene Paleontology and Geology of Brunet et a/. 3 announce the discovery they are 6,000 km apart. Sahabi (eds Boaz, N. T., EI-Arnati, A., Gaziry, A. W., de Heinzel in, J. & Boaz, D. D.) 153-181 (Liss, New York, of an australopithecine-like mandible, The hominid mandible from Chad is 1987). NATURE · VOL 378 · 16 NOVEMBER 1995 239 © 1995 Nature Publishing Group.