In 1857, guided by the flickering light of a candle deep in a cave at Naracoorte in South Australia, the Reverend Julian Tenison-Woods stumbled across thousands of tiny bones of rodents and small marsupials buried at the base of crystal columns.
Without knowing it, Woods had found a time machine of sorts – a record of biodiversity and environment spanning more than half a million years.
Now Naracoorte Caves are known as one of the world’s best fossil sites, a place where marsupial lions, enormous kangaroos and giant monitor lizards met their deaths and were preserved by layers of sand.
But the caves captured more than just giants. Clues to Naracoorte’s past environment are also preserved in plant fossils, sediments and calcite formations.
Big marsupials with bite: Australia’s megafauna
Global scientific attention first focused on Naracoorte after 1969, when cave explorers entered relatively inaccessible limestone chambers. After squeezing their way through an impossibly tight gap in Victoria Cave, they discovered the palaeontological equivalent of King Tutankhamen’s tomb.
Scattered across the red sediment floor of a vast chamber were countless skulls and jaws of Australia’s lost giants, the megafauna.
The find created a buzz worldwide and set the stage for a scientific journey of discovery that has unfolded over the past four decades.
Preserved within the deposits are fossils from a suite of megafauna species including heavyweight plant eaters such as Zygomaturus trilobus, short-faced leaf-eating kangaroos such as Procoptodon goliah, and the five-metre snake Wonambi naracoortensis. The most famous of these is the marsupial lion Thylacoleo carnifex. The most spectacular fossils from this king of the Pleistocene forests have come from Naracoorte.
The reign of these amazing animals came to an end around 45,000 years ago, with the precise cause for their extinction still a hot topic for debate.