Archaeological and Paleontological Research in Central Flores, East Indonesia: Results of Fieldwork 1997-98
Morwood, M. J., Aziz, F., O'Sullivan, P., Nasruddin, Hobbs, D. R., Raza, A.,, Antiquity
Claims for Homo erectus on Flores were first made by Fr. Verhoeven, a Dutch priest and amateur archaeologist, who excavated fossil sites in the region (Verhoeven 1968; Maringer & Verhoeven 1970a; 1970b). He reported stone artefacts at Mata Menge, Boa Lesa and Lembahmenge, and concluded that they were about 750,000 years old on the basis of their association in the fossil deposits with Stegodon, an ancestral elephant species.
The range of evidence presented for his claims was generally judged inconclusive because of doubts about the identification of the stones nominated as artefacts, the uncertain stratigraphic association between these and Stegodon fossils, and the age of the strata (e.g. Allen 1991; Bellwood 1985: 66).
Palaeontological research undertaken by an Indonesian-Dutch team replicated Verhoeven's findings. They reported stone artefacts with the remains of Stegodon at Mata Menge (van den Bergh et al 1996: 32-4) and, on the basis of preliminary work, reported a similar association at Dozu Dhalu (van den Bergh & Aziz 1994: 22; van den Bergh 1997: 249).
Furthermore, their excavation at the stratigraphically older site of Tangi Talo, which lacked associated stone artefacts, revealed that there had been a major turn-over in fauna: Tangi Talo contained the remains of pygmy Stegodon (S. sondaari), giant tortoise (Geochelone sp.) and Komodo dragon (Varanus komodoensis), whereas Mata Menge had large Stegodon (S. trigoncephalus florensis), crocodile and giant rat (Hooijeromis nusatenggara). Sondaar (1987) argued that this faunal turn-over resulted from the arrival of a new predator, H. erectus. Palaeomagnetic determinations from Tangi Talo and Mata Menge suggested that the former was 900,000 years old and the latter 'slightly less than' 730,000 (Sondaar et al. 1994: 1260).
Reaction to these claims was muted, and where published, generally cautious (e.g. Bellwood 1997: 67-8). The major impediments to general acceptance of the conclusions were three-fold: the identification of stone artefacts, the lack of taphonomic detail, and the chronological ambivalence of a palaeo-magnetic transition 3 m below the Mata Menge fossil/artefact deposit.
More recent work has shown that stone artefacts definitely occur in situ at Mata Mange (Morwood et al. 1997), while fission track dates of 880,000-800,000 and 900,000 years for Mata Menge and Tangi Talo, respectively, show that both sites are of Early Pleistocene age (Morwood et al. 1998). These findings have significance for assessing the capabilities of early hominids, for their dispersal and for insular evolutionary processes.
Here we present the results of excavations at two of the sites where stone artefacts were said to be in primary association with Middle Pleistocene faunal remains - Boa Lesa and Dozu Dhalu. These are discussed in the light of regional site-survey data. In both cases our aims included:
a To record the stratigraphy and other information on the context of deposition.
b To ascertain whether stone artefacts occur in situ in the deposits associated with fossils, as claimed by previous researchers.
c To collect geological samples for dating, grain-size analysis and palynology.
d To recover a representative sample of stone artefacts and/or fossils.
Evidence for early hominid presence on Flores comes from the Soa Basin on the upper Ae Sissa River [ILLUSTRATION FOR FIGURE 1 OMITTED]. The basin is about 35x22 km in size and is almost entirely surrounded by mountains and active volcanoes. There is one deeply incised river outlet.
The work of Hartono (1961) provided a useful framework for establishing the general and specific geological context of the sites. He identified and mapped three basic stratigraphic units in the study area and our work has added much detail.
The basal material of the Soa Basin is an andesitic breccia termed the Ola Kile Formation. …