Instead of only excavating 'trophy specimens' such as giant kangaroos and wombats, the researchers from Queensland University of Technology (QUT) and Queensland Museum performed the first systematic analysis of a site in the fossil rich Darling Downs region of south-eastern Queensland.
Reported in the journal Memoirs of the Queensland Museum tomorrow (Tuesday 31 May) they found smaller species, dependent on a wetter environment, had also disappeared.
By systematically analysing a 10 metre deep section of creek bed, the team uncovered 44 species, ranging from land snails, frogs, lizards and small mammals to giant wombats and kangaroos including many species previously unknown to have occurred in the Darling Downs fossil record.
The results suggest that the extinction of Darling Downs megafauna was caused by a massive shift in climate rather than by the arrival of humans who over hunted animals or destroyed habitats by burning the landscape.
The findings, which were unearthed with the help of amateur fossil hunter, Ian Sobbe, are of particular significance because the Darling Downs fossil deposits are among the youngest Australian megafauna deposits - laid down on the cusp of the extinction event.
PhD researcher Gilbert Price, of QUT's School of Natural Resource Science who led the study, says:
"Unravelling the cause of the late Ice Age extinction has occupied scientists for centuries. It is essential to know if the risks faced by species and ecosystems today are the same as those in the past.
"If we can document past environmental change and its influence on the extinction of species, it might have predictive value in estimating the effects of possible future climate chang