An ancient footprint preserved in replica, with a human hand providing scale.
Source: Museum Victoria
The 40th anniversary of the first moon landing is being celebrated around the world this month. However a different set of giant steps – more local and far more ancient – have landed at Melbourne Museum.
Museum Victoria preparators recently cast replicas of some incredible megafauna tracks in Victoria's west. The fossilised footprints were left around 120,000 years ago by several animals, including giant wallabies and wombats. At that time, the area had much volcanic activity, and the layer of volcanic ash in which these animals walked has preserved their footprints in exquisite detail. Usually covered by water, the tracks have been exposed during the current drought.
To create the replicas, a team of preparators and paleontologists selected the best sets of tracks and cleaned out silt and mud. They used liquid silicon to create detailed moulds and reinforced them with gauze and fibreglass. After careful removal, the moulds were taken to a factory and used to produce polyurethane casts. A timber frame provides support, and the natural surface of the rock was reproduced by expert painting.
The footprints are a fantastic reference for ichnologists – paleontologists who study animal behaviour though preserved traces such as eggs, burrows and tracks. Much can be learned about these long-dead animals, such as how they moved and how heavy they were, through close examination of their tracks. The site is under investigation by Dr Stephen Carey from the University of Ballarat, Aaron Camens from the University of Adelaide, and David Pickering from Museum Victoria. In addition to the tracks, there are many fossilised bones at the site. These bones do not make up complete skeletons and they have a slightly polished appearance, which suggests that they washed into the lake from nearby areas.
Two sets of replicas were cast; one will reside at the University of Ballarat, and the other will form part of the upcoming 600 Million Years: Victoria Evolves exhibition which is due to open at Melbourne Museum in 2010. Until then, fans of megafauna can see skeletons of Megalania, Genyornis and Diprotodon at Melbourne Museum’s Dinosaur Walk exhibition.
Also available is a new book from Museum Victoria entitled Prehistoric Giants: the Megafauna of Australia. It includes magnificent illustrations by Peter Trusler that were featured on a set of stamps released in 2008 by Australia Post. The book was launched at Melbourne Museum in June with talks by author Danielle Clode and Dinosaur Walk curator Wayne Gerdtz about why these animals grew so large and what we know about them.