Aboriginal Bark Paintings
Although aboriginal culture goes back 65,000 years, bark paintings are a relatively recent innovation dating to the early 20th century.  The bark paintings were done with natural pigments—ochres, charcoal, and white clay—and natural binders on bark, often with a crosshatch design, and they frequently tell a story.   The works have also been done on composition board, andIn the last several decades increasingly in acrylics on canvas.
The Bark Salon at the National Gallery of Victoria has over 150 works.

The National Galley of Australia in Canberra has an amazing collection.
Nym Bunduk, "Map of Murrinh-Patha country, 1" (1959), painting in natural earth pigments, watercolour on composition board, is at the National Gallery of Australia (>).
George Milpurrurru's "The goose egg hunt" (1981), done with natural earth pigments on eucalyptus bark, is at the National Gallery of
Australia (>).

See also:
"First Nations."  National Gallery of Australia.
Wally Caruana.  "History of bark painting."  National Museum of Australia.
Cherie Beach.  "Arnhem Land art 'detectives' helping to discover who painted these priceless works."  ABC Radio Darwin, 5 June 2022.