Aboriginal Settlement of the Dry Interior

Australia: The Land Where Time Began

Aboriginal Settlement of the Dry Interior

The occupation of the arid interior of Australia more than 40,000 years ago is indicated by evidence recovered from Puritjarra. The spread of humans across the different landscapes of the interior of the continent, especially environments that are arid or semi-arid, has puzzled researchers. It was predicted in the middle of the 20^th century (Birdsell, 1957) that humans took between 1,300 and 2,200 years to occupy the entire continent. Birdsell estimated the time it took from first settlement to settlement of the arid interior based on the distance from the arrival point/points, but did not consider the implications involved in the settlement of different environments. According to Hiscock the nature and distribution of resources and the suitability of their technology in new environments as well as economic strategies in those unfamiliar environments should also be considered because of the difficulties faced by humans entering every new environment. More recent models of the initial settlement of the interior of the take account of environmental differences over time and space.

There have been 2 ways used to portray humans moving to the interior.

· Biogeographic descriptions of regional differences in environment and the effects they have on human settlement. This is the approach exemplified by the ‘refuge, corridor & barrier model (Veth, 1989),

· A description of the chronological changes in conditions that confront foragers is typified by the ‘desert transformation’ model (Hiscock & Wallis, 2005).

These approaches are complementary, together offering an insight into the timing and nature of early settlement across the interior.

Considering a biogeographic framework, the barrier environments model proposed much of the inland was occupied by early foragers, though they avoided landscapes such as sand ridge deserts. Ecological principles were employed by Veth to define 3 categories of landscape: uplands, sandridge deserts and corridors. Veth’s argument was that it was difficult for the colonists to occupy the major sand ridge deserts, such as the Great Sandy Desert, Great Victoria Desert and the Simpson Desert, as they are poor in resources and often don’t have drainage patterns that are well defined. He argued (Veth, 1989) that as no archaeological evidence had been found in these deserts that dated to the Last Glacial Maximum (LGM) they had been barriers to the movement and settlement of humans. He contended that piedmont/montane uplands and riverine/gorge systems provided networks of reliable water sources that had drainage systems that were less sensitive to climate change. It was easier for foragers to inhabit these landscapes, even in times when there was low and irregular precipitation, and it was hypothesised by Veth that they served as places of refuge for human groups during the Pleistocene. The category termed ‘corridors’, a 3^rd biogeographic category, incorporated all other areas, such as gibber plains. Veth suggests corridors may have been routes for settlement in some periods, though have acted as barriers in other periods, depending on the climatic conditions.

Though coarse-grained descriptions of environmental differences are provided by these categories, environmental variation is obscured by their large scale, with the result that within these corridors, with water-poor localities within montane or upland zones, or small refuge areas, are hidden. Lawn Hill is an example of a refuge area within a corridor zone. On a continental scale Veth’s model is nevertheless congruent with evidence on the location of archaeological sites that are earlier than 35,000 BP revealing the pattern that is predicted by Veth’s model (data from Smith & Sharp, 1992; O’Connell & Allen, 2004). Later in the Pleistocene, after 25,000 BP, limited use of marginal sandy deserts occurred (O’Connell et al., 1998), though there is little evidence of use of sand ridge deserts earlier than 35,000 BP. Earlier than 40,000 BP there is evidence at Puritjarra that ochre was being transported across dune fields from distant sources, which Hiscock suggests may indicate that the sandy landscapes was occupied, though it might alternatively show that foragers were based in montane environments nearby, living entirely in sand ridge deserts (M.A. Smith et al., 1998). In regions of only sand ridge and flat stony deserts, and no montane regions, no evidence for early occupation has been found; it has even been suggested that at Lake Eyre South occupation did not begin until the Holocene (Hughes & Hiscock, 2005). Hiscock suggests that as a consequence sandy landscapes may have been obstacles to occupation even in the earliest phase of settlement. Therefore, though settlement was widespread in the Pleistocene it appears it was not uniform across the continent, with early foragers emphasising the exploitation of specific environments and features.

According to Hiscock it is implied by this that foragers in the Pleistocene did not have a system of settlement similar to that of Aboriginal people in the sandy deserts in the 20^th century. The paradox about using ethnographic information about recent desert dwellers in order to reconstruct initial settlement of arid and semi-arid environments is revealed by this. The intensive use of vegetable foods and seeds, and maintenance of long distance social networks that involve reciprocity and right to territorial access is emphasised in images of historical Aboriginal desert life (e.g. Gould, 1977, 1980; Tonkinson, 1991). Strategies such as these require neighbouring groups and a detailed knowledge of the food resources available. Aboriginal desert dwellers of the historical period were renowned for their intimate knowledge of landscapes and for their reciprocal social arrangements with their neighbours. According to Hiscock these features cannot, however, been traits possessed by the colonisers of desert landscapes. The early colonisers who explored inland Australia had no knowledge of the terrain or distribution of resources within the terrains they were exploring, and they were not surrounded by neighbours. The subsistence and economic strategies of the original settlers of the deserts must have been different from those of the Aboriginals of the historic period.

An explanation of a possible way in which the early settlers occupied the interior without the strategies used by Aboriginals in the historic period has been offered (Hiscock & Wallis, 2005), their argument being that much of the interior was occupied in a period of higher rainfall and more abundant surface water and food resources. Their hypothesis was that Aboriginals of the Pleistocene were not fully equipped with a modern adaptation to the desert when they moved into the desert, Rather they moved into many inland regions at times when surface water was more plentiful and climatic conditions were less harsh than they are at the present. The early mobile forager groups would have been enabled by not employing specific tools or a detailed familiarity of the local resources to occupy regions across the inland, while gradually refining their knowledge of resources available in each new environment. It has been suggested (Peter Veth, 2005) that the early settlers would have been able to explore and exploit environments that were not familiar to them by being highly mobile, and it was hypothesised (Clair Smith, 1992) that it would have been easier for the early settlers to disperse across new lands if they were not territorial. After the interior had been settled climate change subsequently made conditions more extreme within arid lands, the inhabitants of these arid lands could then either adapt to the new climatic conditions or move to new areas that were habitable as they didn’t have the problems of neighbouring territories to prevent them from moving. According to the ‘desert transformation’ model (Hiscock & Wallis, 2005) involves the settlement of the interior during a period of favourable environmental conditions, which was followed by modification of economic systems as the climate became drier. According to Hiscock the evidence for early occupation of the inland has been accumulating steadily. In the northwest, at:

· Carpenter’s Gap, the lowest level, where evidence of occupation had been found has been estimated to be 45,000 (43,500-46,500) BP (Fifield et al., 2001);

· Riwi (Balme, 2000) an age of 45,500 (44,000-47,500) BP has been estimated for the lowest level;

· Puritjarra 39,000 (36,500-42,500) BP (M.A. Smith et al., 1997 and further south;

· Allen’s Cave 40,000 (37,000-43,000) BP Roberts et al., 1996)

· At Lake Mungo the stratigraphically lowest level in which artefacts have been found has been estimated to date from at least 46,000-50,000) BP (Bowler et al., 2003);

· Cuddie Springs, (Roberts et al., 2001) the age estimate is 35,500 (32,500-38,500) BP;

· GRE8 Cave, (O’Connell & Allen, 2004), the radiocarbon estimate of 41,500 (37,500-44,500) BP of cultural material.

It was argued (Hiscock & Wallis, 2005) that is shown that humans occupied these sites in widely separated regions of the inland more than 40,000 BP. It is not possible to say whether different regions of inland Australia were settled contemporaneously or sequentially, or to know the rapidity of the dispersal of colonists across the inland, owing to the imprecision of the age estimates. Widespread settlement of humans 40,000-50,000 years ago has, however, been demonstrated and it is suggested by the desert transformation model that colonists occupied the inland landscapes because at that time the environmental conditions were very different from those of the present, which would have allowed the foragers to exploit dry regions of the inland while not yet having the kind of economic system that has been observed historically (Thorley, 1998); Hiscock & Wallis, 2005). When desert regions were first occupied by humans climatic and hydrological conditions were not like those of the present. Conditions were cooler and surface freshwater was more widely available earlier than 35,000-45,000 years ago than in the past 10,000 years. Conditions in the dry interior have become progressively more arid over time.

Many studies have produced evidence for a greater availability of water during the initial phase of human settlement of the Australian continent. E.g. marine cores obtained near Carpenters Gap, sedimentary cores from lakes, and residual evidence of plants at archaeological sites all indicate that precipitation was greater and there were more surface water until 38,000-40,000 years ago (van der Kaars, 1991; Bowler et al., 1998; Wang et al., 1999; Wallis, 2001; Bowler et al., 2003; Pack et al., 2003; Hiscock & Wallis, 2005). There was more summer rainfall in the Lake Eyre Basin before 45,000 years ago (B.J. Johnson et al., 1999), and it is probable there was more rainfall in winter until about 30,000 years ago (Miller et al., 1997; Magee & Miller, 1998). Prior to 30,000-35,000 BP Lake Eyre was wetter than at any later time, with greater rainfall in winter, storms in the north, and as a result of lower temperatures, lower evaporation, and there was a low-level perennial lake was present 30,000-35,000 years ago (Hesse et al, 2004). A long-term trend towards drier conditions in the region of Lake Mungo in southeastern Australia has been documented (Bowler et al., 1998). There was a prolonged lacustral phase with high water levels prior to 42,000-50,000 years ago, following which lake levels reduced and fluctuated, though water bodies were present until 22,000 years ago.

According to Hiscock a general image of the interior into which humans first moved, with the landscapes being remarkable has been provided by environmental information. Seasonal floods and large standing water bodies were common and comparatively predictable up until 40,000-45,000 years ago in many regions that have been characterised as corridors or uplands (Veth, 1989). Though these landscapes were deserts, which were drier than many regions on the margins of the continent, were differed significantly at the time of the first human arrivals in the area from the desert environments of the present, most noticeably in the presence of large permanent water bodies. Availability and predictability of water, as well as other resources, in the ‘lacustral phase’ up until 40,000 BP, was proposed by the desert transformation model (Hiscock & Wallis, 2005), and this would have facilitated the exploration and exploitation of interior landscapes. It was hypothesised that when the ancestral Aboriginal People moved into these lands they employed flexible foraging strategies that focused on hunting a wide range of small-medium sized game such as marsupials, reptiles, fish and mussels. There is no evidence that the larger animal species that were present at that time were hunted intensively. Hiscock suggests exploitation of riverine and lacustral resources was probably an important economic focus in several regions. It was observed (Thorley, 1998) that the images of the early foragers of inland Australia who focused their economy on tropical gorges, large riverine environments that were reliable and rich lake systems is remote from the characterisation of desert dwellers of the recent times in the modern arid landscapes.

According to Hiscock a basis for the emergence of later Pleistocene arid zone economic systems was probably provided by movement of groups of humans into inland landscapes that were not familiar, but were relatively well-watered, earlier than 40,000 BP. A gradual desertification occurred following initial settlement of the interior, which intensified about 35,000 BP. In many areas there was a decline in the available permanent surface water and the amount and reliability of rainfall diminished progressively. As new, more severe desert landscapes developed foraging and social strategies were able to be modified, because the occupiers of these inland areas had accumulated knowledge of their local environment as it changed to a new, drier condition. Based on information and perceptions about the local environment it is probable that new economic and technological strategies were developed. Hiscock suggests it is in this way that pronounced Late Pleistocene drying assisted the foraging groups that had settled the interior, employing flexible, though not specific, terrestrial economies, to develop economic strategies that were more specialised for desert conditions. As a result of early occupation of inland Australia not being traced in detail, partly because of the small amount of evidence that has been uncovered, and in part because the focus of archaeologists has been on dating the early sites rather than interpreting life ways that are represented by the material that has been found in these early archaeological sites. The ‘desert transformation’ model nevertheless removes the paradox of how early colonists could migrate into deserts during the Pleistocene. As Hiscock says, “in important ways modern deserts of Australia came to inland dwelling people, rather than the reverse”.

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