Kangaroo evolution is a barometer of climate change in Australia and could help determine how local fauna may be affected in the future, a new study showed on Wednesday.
Using skeletons of modern and fossil species, a Flinders University paleontologist and a Murdoch University anatomist have pieced together a detailed kangaroo family tree.
Flinders University's Gavin Prideaux said there have been hints of key stages in the evolution of the animals, but their whole story has not been put together until now.
Kangaroos and wallabies have long been recognized as potentially ideal barometers of historical climatic change in Australia, Prideaux told Australian Associated Press.
They have been around for at least 30 million years, but difficulties in working out which species are related and when certain lineages evolved have hampered research for more than a century.
"We are now able to say that many of the key stages within the evolution of the group actually match quite closely with key stages in the evolution of Australia's climate," Prideaux said.
When Australia was covered in forest and wetter and warmer 25 million years ago, small kangaroos lived in the undergrowth.
They took over as one of the dominant animals after Australia started to become drier 15 million years ago.
Getting the kangaroo story together could help scientists look at the impact contemporary climate change will have on Australia's remaining fauna, he said.
"It is very difficult to make any reasonable predictions based on really short-term data. You need long-term data provided by the fossil records on what kind of impact these changes can have on ... Australian animals."
Their findings are published this month in the Zoological Journal of the Linnean Society.