Karen’s current projects

Current research projects

Discovery Grant Project DP1094569 “Drying and dying in Australia: extraordinary creatures and climate change 15 million years ago”

 

Australia’s globally distinctive mammals were confronted 15 million years ago by a climate plunge from lush greenhouse to dry icehouse conditions. In northern Queensland, in the World Heritage-listed cave known as AL90 from the Oligo-Miocene freshwater limestones of Riversleigh, fossil-rich deposits span this interval of change. Entombed in AL90 Site are dozens of extraordinarily well-preserved skulls and articulated skeletons including a growth series from pouch-young to adults of a rare, possibly sloth-like diprotodontid marsupial (Nimbadon lavarackorum) as well as more familiar kangaroos, thylacines and bats.

 

Main research aims:

1) to develop significant new understanding about zygomaturine diprotodontids which were highly diverse, ecologically important marsupials that once dominated Australian faunas. The sample of skulls and skeletons of Nimbadon provides unique opportunities to understand how these strange marsupials grew, interacted and functioned in the forests that covered Riversleigh and much of the rest of Australia during the middle Miocene.

2) to help resolve controversies about the nature of Australia’s palaeoenvironments before (arguably lush greenhouse conditions) and after (arguably dry icehouse conditions) the global mid Miocene climatic oscillation. AL90 includes highly fossiliferous mid Miocene (15 Ma) sediments as well as relatively less fossiliferous late Miocene sediments. These should reflect changing northern Australian palaeoenvironments. Our research will also help align Australian records of biotic change with global palaeoclimatic events and provide a benchmark for measuring the nature and rate of environmental and biotic change that continues to transform our nation.