GEOSEA V Proceedings Vol. II , Geol. Soc. Malaysia, Bulletin 20, August 1986; pp. 269-288 New lights on human evolution in Southeast Asia S.SARTO 0 Department of Geology Institute of Technology Bandung Bandung, Indonesia Abstract: Until about 1980 the ubdivision of Pleistocene human fossils as proposed by von Koenigswald in 1968 was still in use. In the last five years new discoveri es were made of Pleistocene human remains in Java which necessitate the reassessment of our evolutionary insight on human evolution in thi s part of the world. It seems there are two groups of Homo erectus fossils, i.e. : An earl y Homo erect us trinilensis (cf. H. e. erect us), which is morphological primitive and has an age between late Lower Pleistocene and early Middle Pl eistocene. A late Homo erecrus ngandongensis (cf. H.e. soloensis), which is morphologicall y progressive and has an age between late Middle Pleistocene up to the end of Upper Pleistocene. Homo robustus (cf. Pithecanthropus robustus, P. modjokerrensis) is regarded as being on the same hominization stage as Homo habilis of Africa and Pithecanthropus lanrianensis from China. There were two main evolutionary lines among Pleistocene hominid fossils of Southeast Asia, i. e. one of Australopithecus and the other of Homo. The earliest wave of human migration from the Asian main land arri ved in Southeast Asia, particularly in Java. at about 1.8 my. BP. This latter coincided wi th the onset of Gunz glacial. Before this period the Southeast Asian region was still inundated by sea which hampered the southwardly migrational movement of early hu man beings fro m Asia. INTRODUCTION Charles Darwin and Evolution are two intimately connected phrases. In the 19th century when Europe again paid interest to natural sciences after a long period of undergoing dark ages, the brilliant ideas of Darwin concerning organjc evolution were put forward. Hi s concepts on evolution were influenced by outstanding scientist such as Wallace (1823-1913) the evolutionist Thomas Henry Huxley (1825-1895) the taxonomist working in the Pacific area, Mal thus (1766-1834) the sociologist and economist, the botanist Hooker (18 17-1911), Chevalier de Lamarck and Charles Lyell respectively a vertebrate paleontologist and geologist. Two famous publications of Darwin are of fundamentally importance for the science of evolution: 1859 - On the origin of species by means of natural selection or the preservation of favoured races in the stru ggle for I ife. 1871 - The descent of man and selection in relation to sex. Eugene Dubois, as young anatomist, was deeply impressed by Darwin's ideas. He reasoned that should man have evolved from an ape, he must have lost most of his hair covering hi s body. Fw1her he ass umed that human evolution more likely took place in the jungles of the tropical areas where life is difficult, and volcanic outbursts and earthquakes added more misery to their lives. With that idea in mind Dubois drafted himself as a medic in the former Dutch colonial rum y serving in the then known East Indies, now call ed Indonesia. In fact in doing so, without his knowing, he heralded the beginning of the seru·ch for the ancestors of man and into the science of human evolution. 270 S.SARTONO This paper deals with human evolution in the Southeast Asian region with emphasis on Java where most of the fossil finds have been made. Most spectacular is the recent discovery· of two human skull fragments regarded as belonging to the controversial Meganthropus pafaeojavanicus, which is now classified as australopithecine and called Austrafopithecus pafaeojavanicus. THE FOSSIL SITES Until today Southeast Asian Pleistocene human fossils are only found in Java, although their stone artefacts are scattered on many islands of the Southeast As ian Archipelago. In Java, so far, human fossil sites are restricted to Central and Ea tJava i_n Trinil, Kedungbrubus, Ngandong, Sangiran, Perning, Patiayam and Sambungmacan (Figure 1). These will be briefly discussed below. 1. Dubois and Trinil As mentioned above Dubois became a member of the Dutch colonial army serving in the former Dutch East Indies. First he was stationed in Sumatra, where he began digging in caves to find human fossils, but in vain. Then he was transfeiTed to Java and here lucky enough, he got a free hand from the Dutch government to carry out his search and to roam the country. He came to the village Wajak in East Java and recovered two fossi l skulls, called Homo wajakensis. But these skulls were too modern, and surely not the "missing link" he was looking for. Then he anived in Kedungbrubus where he found a mandible fragment regarded as of Pithecanthropus. The specimen is ajuverule of about five years old (Tobias 1966). More to the west he came to the village Trinil on the right bank of Bengawan (River) Solo. Here, at last, he recovered what he was lookjng for. It was a fossil skull named later by himself as Pithecanthropus (Dubois 1924). At the time in which the first skull of Pithecanthropus erect us was recovered by Eugene Dubois, it seemed that the scientific world was not yet ready for such a controversial specimen. Was it human, albeit a primitive one, or an ape? Or was it the "missing-link" which the paleontological world is waiting for? Those are the questions which have haunted scholars in the science of evolution ever since the specimen was found. Earlier a German biologist named Ernst Haeckel coined the name ' Pithecanthropus", or ape-man, in 1889 for a postulated precursor of Homo sapiens, the present-day man. He placed the Pithecanthropus ape-man two steps below modern men in the evolution tree of the primates, and in doing so he added also the specific designation of alalus, or speechless so to say, because he was of the opinion that the ability to talk is an exclusive human trait. Several years after the skull was recovered a thighbone was found, which morphologically is a modern one and eemingly originating from the same formation in which the skull cap was embedded. Based on this thighbone Dubois therefore gave to his specimen the specific name erectus, and hence it became known as Pithecanthropus erectus. It seems that the furor about Dubois' find did not end by naming it Pithecanthropus erectus; it just begun and lasted till today with the end not in sight yet. Many names have been introduced si nce then and various schemes of evolutionary trees suggested for the specimen. N JAVA SEA i SambunQmacon N<;jando <J • • • ) KedunQbrubus • Trinil • ME RAP I A A A LAWU WLIS 0 100 Km INDIAN OCEAN Fig. I Sites of Pleistocene hominids in Java. 272 S. SARTONO Indeed the vast number of publications concerning Pithecanthropus erectus is entirely in contradiction with the one and only specimen. In the meantime synonyms had been proposed which made matters worse. To mention but a few: 1896 Homo pithecanthropus (Manouvrier). 1899 Hylobates giganteus (B irkner, Boule, Bumuller). 1900 Proanthropus (Martin, McGregor, Mollison, Osborn, Schwalbe, Topinard, Weidenreich, Weinert, Wilser). 1902 A bastard between man and ape (Branca). 1909 Hylobates gigas (Krause, Klaatsch, Obermaier, Sergi, Voltz, Waldeyer, Virchow). 1921 A chimpanzee (Rahmstorm). 1921 A small Neanderthal (Mair). 1922 Homo sapiens erectus (Gieseler, Gregory, Haeckel, Hardlicka, Keith, Kleinschmidt). 1922 Homo trinilensis (Abel, Alsberg). 1924 A deformed Homo sapiens (M inakow). 1932 Praehomo asiaticus javanensis (Black, Dubois, von Eickstedt). As will be known, after the year 1932 the name Pithecanthropus erectus is usually assigned to the specimen. Tllis lasted till about 1950 when it became known asHomo erectus. 2. ter Haar and Ngandong Ngandong is a hamlet on the left bank ofBengawan Solo. TerHaar, who was a geologist, was undertaking geologic mapping work in the area when he ran into the site (ter Haar 1934). This Upper Pleistocene river terrace contained not less than eleven skulls. These are described and named as Homo (Javanthropus) soloensis (Oppenoorth 1932). Some scholars call it simply Solo Man (Weidenreich 1951), neanderthaloid (LeGros Clark 1964), Pithe­ canthropus soloensis (Jacob 1973) and Pithecanthropus ngandongensis (Sartono 1975a). 3. von Koenigswald and Sangiran During his many trips around Java, Dubois in fact also arrived in Sangiran, but curiously enough he did not find any human fossils in the area. It was von Koenigswald who got the merit of having his name coined with Sangiran, so far the most richest early human site in Southeast Asia. He not only recovered Pithecanthropus erectus specimens (Koenigswald 1940), but other species too: modjokertensis (Koenigswald 1968) and dub ius (Koenigswald 1968), as well as the famous but controversial Menganthropus palaeojavanicus (Koe­ nigswald 1941: in Weidenreich 1945). Outside Sang iran he recovered the fossil Homo modjokertensis in Perning near Mojokerto in East Java (Koenigswald 1940), which he thought the same as Pithecanthropus modjok­ ertensis because both of them are Lower Pleistocene in age. 4. Post World War IT recoveries After World War II and-the following political turbulence in Indonesia had ended, the search for fossil men continued with more sucess than before. Not only more specimen were NEW LIGHTS ON HUMA N EVOLUTION Ll\1 SOUTHEAST ASIA 273 recovered but also the number of each species had increased considerably (Figure 2). Most important of those specimens are two skull fragments regarded as Meganthropus (Sartono 1982) with certain morphological features known of australopithecinae. These may support the opinion of Robinson (1954) which suggested thatMeganthropus palaeojavanicus should be called Australopithecus palaeojavanicus. As will be discussed later, using the specimens recovered so far, it is able to propose an evolutionary scheme ofhominids found in Java which shows the existence oftwo genera i.e. Australopithecus and Homo.