![]() Although CT technology, called microCT for very small objects, has existed for decades, it’s been troublesome to scan many samples at once.Įach specimen must remain still while being X-rayed and then be individually identified and labelled amongst dozens of other fossils. This involves taking thousands of X-rays of an object and combining them into a 3D volume. These are some of what were 73 bones able to be scanned in a single tube. Using simple, inexpensive materials like pharmaceutical capsules and paper straws, we can secure hundreds of tiny fossils in a single tube so we can scan them together using X-ray computed tomography (CT scanning). This is where our newly developed high-throughput method comes in. However, piecing together an accurate story from these fossils is difficult, because not only are they small and broken, we also have thousands of them to sort through and identify. ![]() These fossils, now carefully housed in museum collections, are the fruits of countless hours of excavating in places like Capricorn Caves in central-eastern Queensland. Iron and Ice: How life survived snowball EarthĮach bone tells a story of who that individual was and who it lived alongside – each bone is a data point into the past. The bits they don’t end up eating fall to the cave floor and, over tens of thousands of years, these layers of bones accumulate into a nightly record of life, preserved for palaeontologists to unravel. Thankfully, owls and ghost bats that roost in caves have been doing us a favour by capturing lizards and frogs as their prized food, night after night, for millennia. And for this we need teeth and bones – lots and lots of them. Picture: Rochelle Lawrenceīut to do so, we first need to know what species the fossils belong to. The Colosseum Chamber excavation pit inside the Capricorn Caves where thousands of lizard and frog fossils have been collected. To identify the conditions under which these animals evolved, we need to compare the past herpetofauna with those from the present day.įossils offer a unique opportunity to do that, providing direct evidence of what kinds of species existed before major environmental change compared to those that survived it. But, it’s our lizards and frogs that boast greater species diversity and can tell us more about how animals adapted to or succumbed to past environmental upheaval. Our knowledge of Australia’s recent prehistory is largely focused on our cute and cuddly creatures – the mammals – including marsupials and monotremes. Much of the herpetofauna found here in Australia aren’t found anywhere else. They have adapted over millions of years through past climatic changes, including intensifying aridity, Ice Ages and the arrival of Asian species. Many of Australia’s reptiles and amphibians, known collectively as herpetofauna, are threatened with extinction due to global warming, habitat loss and invasive predators. 3D scanning reveals new (but extinct) star fish This is important because understanding the contexts that generated evolutionary diversity in the past may help to reveal how species will respond to climate change in the future. With the exception of goannas, that once grew up to six metres long, these mostly small animals leave only tiny fragments of their bodies behind when they die, making fossilisation an unlikely prospect.īut, in some circumstances, when particular conditions are right, these tiny remains fossilise and can be preserved for millions of years underground.Ī major challenge for palaeontologists, whose job it is to identify and interpret fossils, has been to use these tiny remains to learn more about Australia’s natural history. Picture: Getty ImagesĪ lack of a fossil record is mostly to blame. Australia is host to a huge number of different species of lizard and frog like the Wild Barking Gecko. Yet we have little understanding of when, how or why this great diversity came to be. ![]() This extraordinary diversity, with nearly 900 species and counting, suggests a complex evolutionary past. It is no surprise that Australia is sometimes called “ The Land of the Lizards”.ĭNA analysis has revealed hundreds of new lizard species in the last decades, with more being constantly discovered. ![]()
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