Developmental age and taxonomic affinity of the Mojokerto child,Java, Indonesia

An increasing number of claims place hominids outside Africa and deep in Southeast Asia at about the same time that Homo erectus first appears in Africa. The most complete of the early specimens is the partial child's calvaria from Mojokerto (Perning I), Java, Indonesia. Discovered in 1936, the child has been assigned to Australopithecus and multiple species of Homo, including H. modjokertensis, and given developmental ages ranging from 1–8 years. This study systematically assesses Mojokerto relative to modern human and fossil hominid growth series and relative to adult fossil hominids. Cranial base and vault comparisons between Mojokerto and H. sapiens sapiens (Hss) (n = 56), Neandertal (n = 4), and H. erectus (n = 4) juveniles suggest a developmental age range between 4 and 6 years. This range is based in part on new standards for assessing the relative development of the glenoid fossa. Regression analyses of vault arcs and chords indicate that H. erectus juveniles have more rounded frontals and less angulated occipitals than their adult counterparts, whereas Hss juveniles do not show these differences relative to adults. The growth of the cranial superstructures and face appear critical to creating differences in vault contours between H. erectus and Hss. In comparison with adult H. erectus and early Homo (n = 27) and adult Hss (n = 179), the Mojokerto child is best considered a juvenile H. erectus on the basis of synapomorphies of the cranial vault, particularly a metopic eminence and occipital torus, as well as a suite of characters that describe but do not define H. erectus, including obelion depression, supratoral gutter, postorbital constriction, mastoid fissure, lack of sphenoid contribution to glenoid fossa, and length and breadth ratios of the temporomandibular joint. Mojokerto is similar to other juvenile H. erectus in the degree of development of its cranial superstructures and its vault contours relative to adult Indonesian specimens. The synapomorphies which Mojokerto shares with H. erectus are often considered autapomorphies of Asian H. erectus and confirm the early establishment and long-term continuity of the Asian H. erectus bauplan. This continuity does not, however, necessarily reflect on the pattern of origin of modern humans in the region. Am J Phys Anthropol 102:497–514, 1997. © 1997 Wiley-Liss, Inc.     

Homo floresiensis: a cladistic analysis

The announcement of a new species, Homo floresiensis, a primitive hominin that survived until relatively recent times is an enormous challenge to paradigms of human evolution. Until this announcement, the dominant paradigm stipulated that: 1) only more derived hominins had emerged from Africa, and 2) H. sapiens was the only hominin since the demise of Homo erectus and Homo neanderthalensis. Resistance to H. floresiensis has been intense, and debate centers on two sets of competing hypotheses: 1) that it is a primitive hominin, and 2) that it is a modern human, either a pygmoid form or a pathological individual. Despite a range of analytical techniques having been applied to the question, no resolution has been reached. Here, we use cladistic analysis, a tool that has not, until now, been applied to the problem, to establish the phylogenetic position of the species. Our results produce two equally parsimonious phylogenetic trees. The first suggests that H. floresiensis is an early hominin that emerged after Homo rudolfensis (1.86 Ma) but before H. habilis (1.66 Ma, or after 1.9 Ma if the earlier chronology for H. habilis is retained). The second tree indicates H. floresiensis branched after Homo habilis.     

Dental microwear and diets of African early Homo

Conventional wisdom ties the origin and early evolution of the genus Homo to environmental changes that occurred near the end of the Pliocene. The basic idea is that changing habitats led to new diets emphasizing savanna resources, such as herd mammals or underground storage organs. Fossil teeth provide the most direct evidence available for evaluating this theory. In this paper, we present a comprehensive study of dental microwear in Plio-Pleistocene Homo from Africa. We examined all available cheek teeth from Ethiopia, Kenya, Tanzania, Malawi, and South Africa and found 18 that preserved antemortem microwear. Microwear features were measured and compared for these specimens and a baseline series of five extant primate species (Cebus apella, Gorilla gorilla, Lophocebus albigena, Pan troglodytes, and Papio ursinus) and two protohistoric human foraging groups (Aleut and Arikara) with documented differences in diet and subsistence strategies. Results confirmed that dental microwear reflects diet, such that hard-object specialists tend to have more large microwear pits, whereas tough food eaters usually have more striations and smaller microwear features. Early Homo specimens clustered with baseline groups that do not prefer fracture resistant foods. Still, Homo erectus and individuals from Swartkrans Member 1 had more small pits than Homo habilis and specimens from Sterkfontein Member 5C. These results suggest that none of the early Homo groups specialized on very hard or tough foods, but that H. erectus and Swartkrans Member 1 individuals ate, at least occasionally, more brittle or tough items than other fossil hominins studied.     

Stone implements from Java and Flores: A history of the discoveries

In 1970, Verhoeven and Maringer found stone implements on the surface of Mengeruda (an area including the sites Boaleza, Lembahmenge and Matamenge) and Ola Bula on Flores, which were similar to those found in Sangiran by von Koenigswald and Ghosh on Java. This, among other things, led von Koenigswald and Ghosh to compare the findings from Flores with those from Java, the Ngebung site. They thought that the Stegodon fossil from Mengeruda was the same species as the one from Java and, therefore, of a similar age. von Koenigswald and Ghosh were the first to accept that the artefact findings of Flores were in situ. They drew the right conclusions regarding the crossing to Flores by Homo erectus. And their ideas have now, almost 40 years later, been confirmed by the find of Homo floresiensis on Flores.     

Conclusions: implications of the Liang Bua excavations for hominin evolution and biogeography

Excavations at Liang Bua, on the Indonesian island of Flores, have yielded a stratified sequence of stone artifacts and faunal remains spanning the last 95 k.yr., which includes the skeletal remains of two human species, Homo sapiens in the Holocene and Homo floresiensis in the Pleistocene. This paper summarizes and focuses on some of the evidence for Homo floresiensis in context, as presented in this Special Issue edition of the Journal of Human Evolution and elsewhere. Attempts to dismiss the Pleistocene hominins (and the type specimen LB1 in particular) as pathological pygmy humans are not compatible with detailed analyses of the skull, teeth, brain endocast, and postcranium. We initially concluded that H. floresiensis may have evolved by insular dwarfing of a larger-bodied hominin species over 880 k.yr. or more. However, recovery of additional specimens and the numerous primitive morphological traits seen throughout the skeleton suggest instead that it is more likely to be a late representative of a small-bodied lineage that exited Africa before the emergence of Homo erectus sensu lato. Homo floresiensis is clearly not an australopithecine, but does retain many aspects of anatomy (and perhaps behavior) that are probably plesiomorphic for the genus Homo. We also discuss some of the other implications of this tiny, endemic species for early hominin dispersal and evolution (e.g., for the “Out of Africa 1” paradigm and more specifically for colonizing Southeast Asia), and we present options for future research in the region.     

Are the small human-like fossils found on Flores human endemic cretins?

Fossils from Liang Bua (LB) on Flores, Indonesia, including a nearly complete skeleton (LB1) dated to 18kyr BP, were assigned to a new species, Homo floresiensis. We hypothesize that these individuals are myxoedematous endemic (ME) cretins, part of an inland population of (mostly unaffected) Homo sapiens. ME cretins are born without a functioning thyroid; their congenital hypothyroidism leads to severe dwarfism and reduced brain size, but less severe mental retardation and motor disability than neurological endemic cretins. We show that the fossils display many signs of congenital hypothyroidism, including enlarged pituitary fossa, and that distinctive primitive features of LB1 such as the double rooted lower premolar and the primitive wrist morphology are consistent with the hypothesis. We find that the null hypothesis (that LB1 is not a cretin) is rejected by the pituitary fossa size of LB1, and by multivariate analyses of cranial measures. We show that critical environmental factors were potentially present on Flores, how remains of cretins but not of unaffected individuals could be preserved in caves, and that extant oral traditions may provide a record of cretinism.     

Preface: research at Liang Bua, Flores, Indonesia

Excavations at Liang Bua, Flores, Indonesia, have yielded evidence for an endemic human species, Homo floresiensis, a population that occupied the cave between ∼95-17 ka. This discovery has major implications for early hominin evolution and dispersal in Africa and Asia, attracting worldwide interest. This preface describes the rationale for the excavations in historical, geographical, and wider research contexts, as well as the methods used. It also introduces the other papers on aspects of Liang Bua research that feature in this edition of the Journal of Human Evolution.     

New dates for the Fontéchevade (Charente, France) Homo remains

Homo I from the site of Fontéchevade, France, has long been an anomaly in the European fossil record. The specimen is a fragment of human frontal bone that lacks a supraorbital torus and appears to belong to an anatomically modern Homo sapiens. However, the level from which it was recovered in 1947 was dated on the basis of associated faunal and lithic material to the last interglacial or earlier. As a result, Homo I has been interpreted, among other things, as a representative of a pre-sapiens lineage in Europe. This paper reports on recent ESR and radiocarbon dates that indicate that the specimen almost certainly dates to oxygen isotope stage 3, which brings it in line with other evidence for the entry of modern Homo sapiens into Europe.     

Human talus bones from the Middle Pleistocene site of Sima de los Huesos (Sierra de Atapuerca,Burgos, Spain)

Here we present and describe comparatively 25 talus bones from the Middle Pleistocene site of the Sima de los Huesos (SH) (Sierra de Atapuerca, Burgos, Spain). These tali belong to 14 individuals (11 adult and three immature). Although variation among Middle and Late Pleistocene tali tends to be subtle, this study has identified unique morphological characteristics of the SH tali. They are vertically shorter than those of Late Pleistocene Homo sapiens, and show a shorter head and a broader lateral malleolar facet than all of the samples. Moreover, a few shared characters with Neanderthals are consistent with the hypothesis that the SH population and Neanderthals are sister groups. These shared characters are a broad lateral malleolar facet, a trochlear height intermediate between modern humans and Late Pleistocene H. sapiens, and a short middle calcaneal facet. It has been possible to propose sex assignment for the SH tali based on their size. Stature estimates based on these fossils give a mean stature of 174.4 cm for males and 161.9 cm for females, similar to that obtained based on the long bones from this same site.     

郧县人类头骨化石与周口店直立人头骨的形态比较

对郧县人类头骨化石与周口店直立人头骨作了形态上的比较以检验直立人特征在郧县头骨化石上的表现情况．比较项目包括眶上圆枕、枕骨圆枕、枕平面与项平面之间的转折情况、眶后收缩、颅骨最大宽位置、颅盖低平情况、前额后倾情况和颅容量．结果表明,在郧县人类头骨化石的这些特征项目中,有的因头骨破损和变形而难以肯定．其余的则应是早期智人的特征．从形态上讲,郧县人类头骨化石目前还难肯定是属于直立人,而有可能属于智人,如果认为“直立人”和“智人”是两个不同的物种的话．     

L’architecture de l’épaule au sein du genre Homo : nouvelles interprétations

The morphology of human clavicles can be estimated by projecting them on two perpendicular planes in order to assess the shapes of their cranial and dorsal primary curvatures. In cranial view no differences in curvature appear within the genus Homo, which means the different species had similar arms elevation capacity, especially in protraction. On the contrary, in dorsal view two clavicles morphologies could be defined. The first one is characterized by two curvatures in dorsal view and is possessed by all Homo species, from Homo habilis to Neanderthal, including Homo ergaster, but not modern human, Upper Paleolithic and anatomically modern human remains, who possess clavicles of the second type, characterized by either one curvature, or two slightly pronounced ones in dorsal view. Clavicles displaying two pronounced curvatures in dorsal view are associated with scapula sitting high on the thorax in regard to modern human. However, shoulder with high scapula on the thorax displays two different kinds of architectures: (i) shoulder with short clavicles associated to scapulas sitting more laterally than those of modern human. This group includes earlier Homo like Homo habilis and Homo ergaster and (ii) shoulder with long clavicles associated to scapulas sitting more dorsally on the thorax, like those of modern human. This group includes Homoantecessor and Neanderthals. In other words, within the genus Homo, three shoulders would have existed. Evolution of the shoulder complex is far more complex than previously thought and the arrival of modern bipedalism was not associated to modern shoulder.     

The “Pithecanthropus IV” diastemata: Malocclusion in a fossil man

The Homo erectus skull fragments collected by von Koenigswald in Java in 1939 and designated by him as Pithecanthropus IV have been a source of ongoing interest because of the unique precence of seemingly simian-like precanine diastemata evident in the restored maxilla. These interdental spaces have posed a paradox because similar gaps are absent in other pithecanthropine remains and in considerably older hominid fossils.I have tested the hypothesis that the skull IV diastemata represent a human occlusal variant; in this paper, I illustrate methods of differential occlusal analysis and describe the multiplicity of factors that may lead to superficially similar maxillary precanine diastemata. Results of analysis of skull IV characteristics suggest that the diastemata were caused by labial displacement of the maxillary incisors because of vertical collapse after loss of the posterior mandibular teeth.     

Cladistic analysis of early Homo crania from Swartkrans and Sterkfontein, South Africa

The phylogenetic relationships of early Pleistocene Homo crania from the South African sites of Swartkrans and Sterkfontein were investigated through cladistic analyses of 99 morphological characters. The Swartkrans Member 1 specimen SK 847 and the Stw 53 cranium from Sterkfontein Member 5A were treated as separate operational taxonomic units (OTUs), distinct from the three species of early Homo-H. erectus, H. habilis, and H. rudolfensis-that are recognized from the Plio-Pleistocene deposits of East Africa. The cladistic analyses differed in the treatment of the South African OTUs (separate Swartkrans and Sterkfontein OTUs vs. a single Swartkrans+Sterkfontein OTU). PAUP 4.0 was used to construct cladograms and address hypotheses about relationships. In the analysis that treated the South African specimens as a single OTU, the position of that OTU was stable as a separate branch on the Homo clade between H. rudolfensis and [H. habilis+(H. erectus+H. sapiens)]. When SK 847 and Stw 53 were treated as separate OTUs, the majority of most parsimonious trees indicated that they were positioned in similar positions as the combined South African Homo OTU; that is, as separate branches between H. rudolfensis and [H. habilis+(H. erectus+H. sapiens)], with the Swartkrans OTU generally occupying a more derived position. The position of the Sterkfontein OTU was more stable than that of the Swartkrans OTU, which was found in several other positions among the minimum length trees. Running the analyses with only those characters preserved by SK 847 and Stw 53 resulted in similar topologies for minimum length trees, although the positions of Stw 53, SK 847, and H. habilis exchanged places in some trees. In no case was an exclusive sister relationship between either South African OTU and a particular species of Homo supported statistically. Both South African OTUs differ from H. habilis in the fewest number of cladistic characters.     

印度纳尔玛达地区发现的粗壮智人化石及其与亚洲直立人的连续性

1999年,在印度西部的纳尔玛达(Narmada)河的一条支流——奥尔桑(Orsang)河谷发现了一具孤立的智人头骨,这对于了解印度人类进化历史和南亚直立人与最古老的亚洲智人(或AMH,解剖学上现代的人)之间的联系有着重要的意义。化石是在古老的河流沉积物中发现的。对主体沉积和颅内沉积物的红外光释光(IRSL)测年结果显示,其年代为3—5万年。然而,对化石的直接测年(放射性碳加速器质谱测年AMS)结果表明,其年代最小为4981—5579年前。头骨被归类为圆颅型智人。头骨上最引人注意的特征是颅外有亚洲直立人头后部很发达的角圆枕。头骨最宽处在下部(颞骨)如直立人,这样的情况从来不见于智人。这可能是由于乳突的气窦化而形成的。乳突上脊发育,从破损的眉间区(20mm)可以看到很宽的额窦。所有这些粗壮的特征都表明Orsang头骨和晚期亚洲直立人之间具有遗传连续性。