Over 500 stunning Arnhem land Maliwawa rock art images - including three rare depictions of bilbies and a dugong - have been documented by Traditional Owners alongside researchers from Griffith University.
The research team collaborated from 2008 to 2018 at 87 different sites to record the images, ranging in age from 6000 to 9400-years-old.
Griffith University's Chair in Rock Art Research, Professor Paul Tacon, led the academic team. Prof Tacon said this Maliwawa style of rock art filled the "missing link" between the already well-known 12,000-year-old early-style "Dynamic Figures" and 4,000-year-old x-ray style figures.
Sites have been located from Awunbarna in the Mount Borradaile area, to the Namunidjbuk clan estate of the Wellington Range.
The Maliwawa art documented included painted red 50cm to life-sized naturalistic humans and kangaroo-like animals, known as macropods, along with other animals.
"Maliwawas are depicted as solitary figures and as part of group scenes showing various activities, and some may have a ceremonial context. Human figures are frequently depicted with animals, especially macropods, and these animal-human relationships appear to be central to the artists' message," Prof Tacon said.
Prof Tacon said the art shows aspects of the artist's cultural beliefs, including headdresses - signifying a ritual context, and an emphasis on interactions between humans and animals.
"Indeed, animals are much more common than in the Dynamic Figure style rock art in terms of percentage of subject matter," he said. "89 per cent of Dynamic Figures are human, whereas only about 42 per cent of Maliwawa Figures are human."
Art at the Awunbarna site depicting what seem to be bilbies surprised the researchers, with the arid and semi-arid loving animals being found in the south of the continent.
Dr Sally K May from Griffith University's Place, Evolution and Rock Art Heritage Unit said Arnhem Land "has not been within [the bilbies'] range in historic times."
"Two of these animals are back-to-back and almost identical in size. The third bilby-like depiction appears to have been made at a different time, and perhaps by a different artist, as it is larger, has a longer snout, has more line infill, and is in a lighter shade of red," said Dr May.
Dr May said there is a possibility that the 'bilbies' are instead Agile Wallabies, Northern Nailtail Wallabies or Short-eared Rock-wallabies. These species are all widespread across Arnhem Land today, "but all of these species have much shorter ears and snouts than extant bilbies and the creatures depicted at Awunbarna."
The art recorded includes the oldest known depiction of a dugong anywhere in the world, but Dr May says it appears to be "out of place."
6,000 to 9,400 years ago, when the art was created, the Arafura Sea would have been far further north than the 15km away it is today.
"It indicates a Maliwawa artist visited the coast," said Dr May, "but the lack of other saltwater fauna may suggest this was not a frequent occurrence."
Back to back
The back-to-back placement of macropods (the kangaroo-like figures), human figures and the 'bilbies' is a style that began with this Maliwawa art style, Professor Tacon said, and then continued with bark paintings and paintings on paper.
Dr Tucon said researchers could not rule out the possibility that a small number of artists produced Maliwawa rock paintings. It is even possible only a couple of artists made most of the images, with one responsible for the mostly-outline style and another responsible for the more filled-in kind.
"At the same time, much art produced after the Maliwawa style demonstrates a remarkable consistency in the manner of depiction and a significant increase in the standardisation of some subject matter such as X-ray fish," said Dr Tucon.
"This has implications for rock art research everywhere in which a style or manner of depiction is suggested to have been made over hundreds of years or millennia."