“Soon after leaving his camp I had the gratification to discover a magnificent specimen of the fan palm growing in the channel of the watercourse, with the drift of floods washed against its stem; its dome-shaped frondage contrasting strangely with the paler green foliage of the gum trees that surrounded it. It was a perfectly new botanical feature to me, nor did I expect to have met it in this latitude.” – Ernest Giles, 30 August 1872
As someone familiar with the vegetation of the flat, dry and hot Australian deserts, the explorer Giles was surprised to discover a valley full of palms in the ranges of Central Australia. The nearest palms occurred hundreds of kilometres to the north, separated by vast expanses of unsuitable dry desert country.
Subsequent researchers have found dozens of similarly isolated species and populations of plants, snails, fish and other vertebrates in the ranges of Central Australia – “the Central Uplands”. Most are separated from their nearest relatives by hundreds or even thousands of kilometres.
How and when did these plants and animals become localised?
One idea is that, just at the Central Uplands have provided a critical refuge for animals and Aboriginal people during droughts, they have also provided a refuge from the great aridification of Australia over far longer timescales. While more...