Ancient Australia: A Polar Dinosaur World 100 Million Years Ago
Palaeontologists have pieced together a picture of Australia during the early Cretaceous Period, when parts of the continent sat within the Antarctic Circle and were home to a diverse range of dinosaurs adapted to polar conditions. At the time, Australia was still attached to Antarctica, featuring a temperate rainforest along a vast rift valley river, with temperatures as low as minus 6 degrees Celsius and months of continuous darkness. The findings highlight Australia as a unique evolutionary refuge where species that died out elsewhere in the world persisted due to its cold, isolated environment.
Around 100 million years ago, south-eastern Australia lay within the Antarctic Circle, hosting a temperate rainforest teeming with dinosaurs adapted to polar life, including swift megaraptors like Australovenator and small herbivores like Leaellynasaura. Palaeontologists from Monash University and Museums Victoria describe dinosaur populations comparable in density to modern kangaroo mobs or emu flocks, with evidence drawn from sites such as Dinosaur Cove, the Dinosaur Dreaming project near Inverloch, and Lightning Ridge in New South Wales. Approximately 50 individual dinosaur species have been identified across Australia, though researchers believe the true number may be considerably higher. The cold conditions also preserved ancient amphibians called temnospondyls, thought to have gone globally extinct some 20 million years earlier, underscoring Australia's role as an evolutionary refuge. Fossil excavation in Australia is notably difficult due to extremely hard rock, requiring drilling and blasting at some sites, and more than 700 volunteers have contributed to digs over the decades. Exploration in Western Australia remains in its early stages, while Queensland has yielded major finds including giant titanosaurs and large marine reptiles. The research continues to reshape understanding of how dinosaurs adapted to high-latitude, low-light environments.
What different sources said
- ABC AustraliaCenter
What Australia would have looked like when the dinosaurs roamed
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