Recent excavations in the interior of the Indonesian part of New Guinea, Irian Jaya (West Irian), have shown that people have lived there since the end of the Pleistocene epoch, in other words for at least ten thousand years. The excavations, by archaeologists from the University of Groningen, took place in the lake area of Ayamaru on the Vogelkop peninsula. The expedition formed part of the interdisciplinary Irian Jaya Studies programme run by the NWO.
The fieldwork was carried out in 1995 by researchers from the Institute of Archaeology at the University of Groningen. They discovered prehistoric habitation strata in two caves (Kria and Toe), finding both tools and the remains of meals consumed there (bones, shells, egg shells). The bones included those of small kangaroos, cuscuses (marsupial "monkeys"), the cassowary bird, fish and snakes. These are somewhat similar to finds made during excavations in Papua New Guinea and Northern Australia. The remains of at least two humans were also found but there were no signs of ritual burial.
Among the more notable finds were dozens of bone "needles" or fish hooks, which have also been found in other parts of Indonesia and in Australia. Hundreds of stone tools were also excavated; these seem to have been used mainly for processing animals the hunters had killed. The archaeologists were also surprised to find a large quantity of red and yellow ochre, but thorough investigation failed to reveal any cave paintings.
The various finds are currently being studied. C14 dating has shown that those from the Kria cave are about 8000 years old. Dating of the material from the lowest levels within the Toe cave by means of the ESR (electron spin resonance) method is still in progress. The animal remains found in this layer indicate that the cave was inhabited at least ten thousand years ago.
Traces of humans dating from around 40 thousand years ago have been found in independent Papua New Guinea, suggesting that the Indonesian part of the island was also inhabited during the Pleistocene. Proof of this assumption is now beginning to emerge.