Australia: The Land Where Time Began

A biography of the Australian continent 

Environments of Australia Before the Arrival of the First Human Settlers

A museum expedition to Lake Mulligan, a corruption of the word malakanha, a word in the language of the Adnyamathanha people for a type of string bag, now known as Lake Callabonna, in 1893 found the bones of many animals of the marsupial megafauna scattered across the salt lake that, in the words of Stirling (1900: III) (Fig. 3.1) ‘which have apparently died where they lie, in hundreds’. The bones of Diprotodon Optatum were the commonest remains found on the dried up lake bed. This large herbivore has been estimated to have grown to about 2.8 tonnes, and was the largest marsupial known (Wroe, et al., 2004). The lake bed proved to be a hazard for the megafauna crossing it to reach nearby springs, the heavy animals becoming trapped when they broke through the dry crust and became trapped when their feet entered the saturated clays below.

By the time the expedition finished at the dig they had collected about 100 animals (Stirling, 1894, 209), among which were the first complete skeletons of Diprotodon and partial skeletons of Genyornis, a large flightless bird, Phascolonus, a giant extinct wombat, Sthenurus, an extinct short-faced kangaroo (Stirling, 1900; Pledge, 1994; Wells & Tedford, 1995). J.W. Gregory summed up the newly arrived at picture of the area of Central Australia in his book The Dead Heart of Australia. In the Lake Eyre Basin there had been a vast inland sea that had dried up as a result of declining rainfall: ‘hot winds swept across the dusty plains, and the once fertile basin of Lake Eyre was blasted into desert’ (Wells, 1906: 150-151).

It has been shown by later research that preserved in these arid landscapes is a palimpsest of ‘lacustral’ or mega-lake phases that vary in age and decline in amplitudes – beginning with palaeodrainage systems and the perennial lakes in the Late Tertiary landscape, about 24 Ma, and more limited rivers that were active and palaeodrainage and palaeolakes during marine isotope stages (MIS) 5 and 7 132-71 thousand years ago; 236-186 thousand years ago, and early in MIS3 60-45 thousand years ago, modest reactivation of semi-arid lake and rive. According to Smith this raises the question, what was the desert like at the time of initial human settlement of the area? Did the first arrivals encounter deserts and dry lands, or was it a landscape of rivers and lakes?

In this chapter Smith reviews more recent work on the age and origin of the deserts in Australia and their biota, and looks in more detail at the environments of the Quaternary in MIS5 before humans settled the region.

Sources & Further reading

1. Smith, Mike, 2013, The Archaeology of Australia’s Deserts, Cambridge University Press