Scientists have hailed the discovery of rare 50-million-year-old crocodile, frogs, fish, and plants fossils at a work site in Brisbane's north as a potential world-first.
At the discovery site on Robinson Road at Geebung where a A$100 million (NZ$117m) rail overpass is being built, Queensland Museum chief executive Professor Suzanne Miller explained the significance of the find.
"This is an incredible ... for Queensland, for Australia and for this local community," Professor Miller said.
"This is utterly unique to science.
"To find this variety of plants and animals that were alive and co-existing 50 million years ago is phenomenal.
"Geologically, around the world there will be a lot of interest in the fossils that have been found."
The fossil remains were discovered by a work crew drilling a hole for a bridge support over an area called the Zillman Waterholes.
About a fortnight ago, the fossils were detected in the "spoil", the oil shale rock and soil found in that hole.
Other fossils were found nearby in what was a low swampy area.
The fossils, about 50 million years old, include a vertebra from the lumbar region of an ancient crocodile that was about five metres long.
The ancient crocodile was an ''amazing find'', Queensland Museum's senior curator of Ancient Envivironments Dr Scott Hocknull said.
''The bone that we have found so far is from the vertebra of the backbone,'' he said.
''When you compare that to a modern day crocodile, you are looking at something of the order of five metres long.''
Dr Hocknull said the crocodile found at Geebung was not the same as today's freshwater or saltwater crocodiles.
''It is probably an extinct animal, an extinct species, but we don't know for sure because it has only been discovered in the last couple of weeks,'' he said.
Fossilised fish similar to a perch, the thigh bone to what could be Australia's oldest frog, and plant life have also been found.
Professor Miller said there was no doubting the significance of the fossil find.
''In the whole of northern Australia this is absolutely unique,'' she said.
''And depending on what we find, because we are just at the beginning of this project, this could be unique in the world.
''This could be some of the earliest mammals ever found.''
Professor Miller said the fossils came from the time after the extinction of the dinosaurs and before Australia's megafauna had evolved.
"It really is a bit of a missing gap in the scientific record about how animals evolved after that massive extinction that killed off the majority of animals on the planet," she said.
"This is a snapshot back in time 50 million years ago when this was all tropical rainforest."
Brisbane Lord Mayor Graham Quirk said it would be appropriate to represent the important fossil find in the final design of the overpass in the future.
Work will not stop at the overpass, but the community has been asked to help sift through 30 cubic metres of dirt to search for more fossils.
- Brisbane Times
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