The latest edition of the Proceedings of the Royal Society of Victoria is now online, featuring a new species of calcareous sponge discovered in Geelong, a spectacular new H5 meteorite in Maryborough, an account of Indigenous meteorological knowledge using stellar scintillation, a reclassification of fossil graptolites from the early Bendigonian, a case for regulated investment in a resilient electricity network, an account of the Bureau of Meteorology’s new extreme heatwave event forecasting service, and a discussion on whether a similar service might be required for cold extremes.
Associate Professor Stephen Gallagher has spent months at sea over the past several years, drilling into the past to obtain a record of Australian geological history. The expedition set out to recover a 5-million-year record of the Australian climate – and surpassed their expectations by uncovering 50 million years. Gallagher was pleasantly surprised at the gems of information discovered on changes to aridity, sea levels, and monsoon cycles that the core samples revealed.
The latest, special issue of the Royal Society of Victoria’s Proceedings concerns itself in detail with a ten-year research program led by a multidisciplinary team from four Victorian universities. The subject is an unusual deposit of shells and burnt stones at Warrnambool, in western Victoria. The site, originally recognised by the late Edmund Gill, is at the mouth of the Hopkins River, known as “Moyjil” by Traditional Owners. It contains the remains of shellfish, crabs and fish in a cemented sand, together with charcoal, blackened stones and features which resemble fireplaces. The dating of the shells, burnt stones and surrounding cemented sands by a variety of methods has established that the deposit was formed about 120,000 years ago, roughly twice the presently accepted age of arrival of people on the Australian continent based on archaeological evidence.
There were once Eucalypts in South America and New Zealand, and South American conifers in Australia. What’s the link?
Antarctica.
Once at the heart of the Gondwana supercontinent, it is unsurprising that Antarctica holds information on plant species that were once common throughout the Southern Hemisphere. First travelling to Antarctica in the summer of 1991-92, Professor Cantrill has since returned eight times to collect data, sometimes spending up to five months at a time out in the field away from shelter and wildlife. Today, the growth and variety of flora in Antarctica is limited, due to the sheer amount of ice cover and inhospitable conditions; however, Professor Cantrill has dug deeper into the past to uncover the southernmost continent’s fossil record, revealing a flourishing environment millions of years ago that supported diverse plant life.
Our evidence for the existence of the different dinosaurs that lived in prehistoric Australia comes from fossilised animal remains and other records of life, such as fossilised footprints. Specific conditions are required for fossilisation to occur, which means that not all life-forms from the Mesozoic Era are preserved, but they are all we have to determine the types of animals that existed during this time. As Swinburne University palaeontologist Dr Stephen Poropat puts it, ‘we need the right rocks!’.
