| Abstract: |
The faunal succession of the Quaternary hominid-bearing deposits of Java has recently become increasingly well-dated. An attempt is being made to correlate major faunal events, including the first occurrences of Homo erectus and Homo sapiens, with global eustatic sea level fluctuations and climatic changes. So far there is no proof for the presence of mammals on Java at 2.4 myr, when the first marked glacio-eustatic sea level lowerings are thought to have occurred. The Satir fauna is the oldest recognizable faunal unit on Java. This fauna has an age of between 2 myr and 1.5 myr and indicates island conditions. Java gradually emerged due to tectonic and volcanic processes during this period. Hominids are still lacking at this stage. Fairly isolated conditions seem to have continued until around 0.8 myr, as suggested by the unbalanced character of the Ci Saat and Trinil faunas, with ages of 1.2 and 0.9 myr respectively. Homo erectus was able to reach Java during this time interval. A major faunal immigration event, leading to a maximum number of medium to large-sized mammals, is represented by the Kedung Brubus faunal stage, corresponding with a marked lowering of eustatic sea level at 0.8 myr. Relatively open and dry conditions prevailed at this stage. Another major faunal turnover event is recorded in the Late Pleistocene Punung fauna on Java and includes Homo sapiens. This drastic environmental change and faunal migration was probably induced by the penultimate glaciation at 135 kyr and the subsequent warm phase from 125 kyr onwards (oxygen-isotopic stages 6 and 5). The Punung fauna was probably established on Java between 110 and 70 kyr when the sea level was fluctuating between 40 and 65 m below present-day sea level, thus permitting overland dispersal to Java, in combination with more warm and humid conditions as compared to the foregoing faunal stages and the glacial maximum at 135 kyr. Between the Late Pleistocene Punung faunal stage and the Holocene faunal stage (as represented by several fossil cave faunas like Wajak, Sampung, Hoekgrot) a large number of extinctions is recorded, while replacement by new immigrations during the last glacial maximum appears to have been limited. The extinctions were probably caused by a number of climatic factors, possibly in combination with habitat alteration by Homo Sapiens.
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