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Temporal changes, within-group variation, and phylogenetic positions of the Early Pleistocene Javanese hominids remain unclear. Recent debate focused on the age of the oldest Javanese hominids, but the argument so far includes little morphological basis for the fossils. To approach these questions, we analyzed a comprehensive dentognathic sample from Sangiran, which includes most of the existing hominid mandibles and teeth from the Early Pleistocene of Java. The sample was divided into chronologically younger and older groups. We examined morphological differences between these chronological groups, and investigated their affinities with other hominid groups from Africa and Eurasia. The results indicated that 1) there are remarkable morphological differences between the chronologically younger and older groups of Java, 2) the chronologically younger group is morphologically advanced, showing a similar degree of dentognathic reduction to that of Middle Pleistocene Chinese H. erectus, and 3) the chronologically older group exhibits some features that are equally primitive as or more primitive than early H. erectus of Africa. These findings suggest that the evolutionary history of early Javanese H. erectus was more dynamic than previously thought. Coupled with recent discoveries of the earliest form of H. erectus from Dmanisi, Georgia, the primitive aspects of the oldest Javanese hominid remains suggest that hominid groups prior to the grade of ca. 1.8-1.5 Ma African early H. erectus dispersed into eastern Eurasia during the earlier Early Pleistocene, although the age of the Javanese hominids themselves is yet to be resolved. Subsequent periods of the Early Pleistocene witnessed remarkable changes in the Javanese hominid record, which are ascribed either to significant in situ evolution or replacement of populations. KEY WORDS hominid evolution; H. erectus; Meganthropus; Pleistocene; Java; mandible; teeth

The Sambungmacan 1 fossil (Java, Indonesia) is assigned to the Homo erectus group. The carbonated matrix contained in this calvaria prevents the analysis of the internal surface. The CT data of the original fossil enables us to observe the conservation and mineralization state and the internal structures. Furthermore, we use the CT data to reconstruct the endocast, which shows that the morphological character of Sambungmacan 1 is close to the Ngandong hominids. [Copyright &y& Elsevier]

This article discusses efforts to use data about racial differences in dentition to identify the racial characteristics of skeletal remains found in Bali, Indonesia. The occlusal patterns in the remains are examined to determine whether they indicate Mongoloid or Australoid racial identity. While there are aspects of this specimen that do not conform to the dentition patterns observed in either race, the researcher concludes that they are closer to Mongoloid patterns.

Abstract: Our current knowledge of the evolution of Homo during the early to middle Pleistocene is far from complete. This is not only because of the small number of fossil samples available, but also due to the scarcity of standardized datasets which are reliable in terms of landmark identification, interobserver error, and other distorting factors. This study aims to accurately describe the cranial morphological changes of H. erectus in Java using a standardized set of measurements taken by the authors from 18 adult crania from Sangiran, Trinil, Sambungmacan, and Ngandong. The identification of some obscure landmarks was aided by the use of micro-CT imaging. While recent studies tend to emphasize evolutionary conservatism in Javanese H. erectus, our results reinforce the theory that chronologically later groups experienced distinct morphological changes in a number of cranial traits. Some of these changes, particularly those related to brain size expansion, are similar to those observed for the genus Homo as a whole, whereas others are apparently unique specializations restricted to Javanese H. erectus. Such morphological specializations in Java include previously undescribed anteroposterior lengthening of the midcranial base and an anterior shift of the posterior temporal muscle, which might have influenced the morphology of the angular torus and supramastoid sulcus. Analyses of morphological variation indicate that the three crania from Sambungmacan variously fill the morphological gap between the chronologically earlier (Bapang-AG, Bapang Formation above the Grenzbank zone in Sangiran) and later (Ngandong) morphotypes of Java. At least one of the Bapang-AG crania, Sangiran 17, also exhibits a few characteristics which potentially indicate evolution toward the Ngandong condition. These strongly suggest the continuous, gradual morphological evolution of Javanese H. erectus from the Bapang-AG to Ngandong periods. The development of some unique features in later Javanese H. erectus supports the hypothesis that this Javanese lineage went extinct without making significant contributions to the ancestry of modern humans. [Copyright &y& Elsevier]

Abstract: Hominid fossils from Ngandong and Sambungmacan, Central Java, Indonesia, are considered to be the most anatomically derived and youngest representatives of Homo erectus. Nondestructive gamma-ray spectrometric dating of three of these Homo erectus skulls showed that all samples underwent uranium leaching. Nevertheless, we could establish minimum age estimates of around 40ka, with an upper age limit of around 60 to 70ka. This means that the Homo erectus of Java very likely survived the Toba eruption and may have been contemporaneous with the earliest Homo sapiens in Southeast Asia and Australasia. [Copyright &y& Elsevier]

Abstract: In the Sangiran dome (Central Java), Homo erectus and mammal fossils in fluviatile context are found in several open-air localities: Tanjung, Sendang Busik, Ngrejeng Plupuh, Grogol Plupuh, and Bukuran. Thirteen taxa of Middle Pleistocene mammals were determined. Lithic tools are rare at these sites. The origin and setting up of these mainly unpublished faunal assemblages are approached by means of methods usually applied to European and African sites in order to understand better the link between humans and animals. The mechanical action of water is responsible for these accumulations and its chemical action for their evolution. [Copyright &y& Elsevier]