A Large Area Archaeological Excavation at Cuddie Springs. (News & Notes)

Article excerpt

Key-words: megafauna, Cuddle Springs, stone artefacts, environmental change

There are three problematic but connected processes during the last 100,000 years of Australian prehistory. These are: the date of initial human settlement; understanding the period of climatic flux culminating in the Last Glacial Maximum around 18-22,000 years ago; and explaining the extinction of the megafauna. The timing of human arrival and population expansion rates are not well understood though most environments were occupied by about 30,000 BP (Mulvaney & Kamminga 1999: 172-89). While the broad framework of climatic change during the Late Pleistocene has been established, localized environmental conditions are more difficult to resolve, particularly in the arid zone. The megafaunal extinctions were a global phenomenon and explanatory models, at least for North America and Australia, depend in different ways on the role of people and climate change (Martin & Klein 1984; Flannery 1994; Choquenot & Bowman 1998; Horton 2000; Head 2000; Wroe & Field 2001).

If we accept recently reported ages of selected megafaunal localities in Australia and West Papua (Roberts et al. 2001) and luminescence dates for a human burial in Australia's southeast (Thorne et al. 1999), then a temporal overlap could be as much as 50,000 years or as little as 10,000 years. Either way it is hard to continue to argue for humans as the primary agent in the extinction process, especially if, as argued by Flannery (1994), human hunters dispatched the megafauna within a short time after their arrival. On the other hand, widely accepted dates for initial human arrival in Australia are from 40-45,000 years and a case could be made that most megafaunal extinctions had already occurred (O'Connell & Allen 1998). In Tasmania, megafauna appear to have become extinct prior to the arrival of people (see Cosgrove & Allen 2001). Ecological data suggest more complex processes at work, whether or not humans are directly implicated. For example, browsers dominate the extinct faunal assemblage in Australia; those that survived underwent phyletic dwarfing and conditions improved for grazers. Furthermore, the same restricted range of species are consistently represented in Late Pleistocene sites. Moreover, it is not clear precisely when, where or how rapidly any particular species became extinct (e.g. Miller et al., 1999; Field & Boles, 1998). Wright (1986) predicted that megafaunal extinctions probably represented a mosaic of events across the continent and as such the evidence needs to be evaluated on a site-by-site basis.

It is rare to find megafaunal bones in association with artefacts anywhere in Australia, and Cuddie Springs is the only known site on the Australian continent where such a stratified record can be found. The aim of this paper is to summarize the results of the 1997 excavations, that provide new data on site structure, and support the broad stratigraphic sequence described in earlier work.

Cuddie Springs is an ephemeral lake in the semi-arid southeast. Flaked stone artefacts are found in direct physical association with a range of megafauna that includes Genyornis newtoni, Diprotodon sp. and Sthenurus sp. in a stratified deposit of lacustrine clays, dated to between ~36,000 and 27,000 years ago (Field & Dodson 1999; Fifield et al. in press; TABLE 1). An environmental record spanning the period of human/megafauna overlap provides a picture of local and regional conditions through time (Field et al. in press).

The human/megafauna association at Cuddle Springs is in a sealed unit between ~1 m and ~1.7 m depth (FIGURE 1). The upper limit, at ~1 m depth, is defined by a deflation pavement probably formed over a 10,000-year period (Field et al. in press). It consists almost entirely of flaked stone artefacts (~50,000 artefacts/cu. m) and is less than 5 cm in depth. The lower limit, at ~1.7 m depth, is a second old land surface described as a beach lag deposit that caps a band of concreted ferruginized sands. …