The open woodlands and scrub of the Western Australian wheatbelt extend across a swathe ofland made green by the winter storm-fronts that brush the continent's southwestern corner. The land was cleared during the course of the twentieth century for agricultural use, mainly the farming ofwheat and sheep. Its extent (160,000 square kilometres) exceeds the total area of many European countries. It is a country that uniquely reprises the history of the planet. To its north, in the Pilbara, there are traces of the earth's original crust, which solidified some 4.3 billion years ago. Here too are found the earliest evidence oflife, the cyanobacteria that excrete the oxygen that turned our sky blue around 3.5 billion years ago. The Yilgarn plateau in the northeastern wheatbelt predates by nearly one billion years the first tectonic fracturing ofthe primordial landmass into the supercontinents ofPangea and Gondwanaland. The Stirling Ranges, which grace the southern wheatbelt, contain fossil evidence of the earliest land- based animals (1.2 billion years ago). Only much later would Antarctica and India (110 million years ago), Africa (80 million years ago) and South America (40 million years ago), detach from Western Australia and begin their migrations to give us such features as the oceans we know and the Himalayan mountains. The region's geographical isolation by ocean and desert, coupled with a temperate yet oscillating climate, have caused a speciation rivalled only in the canopies of tropical rainforests.
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