Fossil spiders, chicads, wasps, plants and fish, give a clear picture of Australia’s numerous rainforest ecosystems during the Miocene, 11 million to 16 million years ago.
“It’s a very important fossil site. It has everything we could expect, exceptionally well – preserved fossils from a time we did not know much about,” said Matthew McCurry, an archaeologist at the Australian Museum of Research. Is the author of a study of the site published in the journal Scientific Advances on Friday.
“The Miocene was the period when most modern Australian contexts were established, so this fossil site is really the origin story of Australia.”
During the Miocene, low rainfall shrunk rainforests around the world, leading to arid lands, the study said.
The site, named McGraths Flat, is located in central Tablelands near the town of Gulkong and was discovered by a local farmer who found fossil leaves in one of his fields, McCarthy said.
McCurry and his colleagues visited the site seven times and excavated.
Storage of well-preserved fossils
“The fossils are amazingly beautiful to look at, and with the use of a microscope you can see the details of the surfaces of the fossils, which are amazingly well preserved,” he said by email.
“Features like individual cells and elements within cells can be found. This level of detail allows us to say more about what these ecosystems were like.”
For example, melanosomes found in fossil feathers mean that scientists can determine the color of feathers. In this case, they believe it ranges from dark brown to black.
McCurry said the site, which originated from iron-rich rock, should be considered Lagerstatte, and was used by many German archaeologists to describe an exceptional site with perfectly preserved fossils.
Plants and organisms were fossilized when iron-rich groundwater was filtered into a bilge or water hole.
McCurry said his favorite fossil was a type of spider, the most well-preserved spider fossil ever found in Australia.
“It’s a very beautiful model.”