(Scale bar = 1mm. Rectangle left shows approximate location of digital micrograph illustrated right).
‘Cherry’ figure. Note that red organisms predominate, but black fungus is also present.
While some rock art fades in hundreds of years, the “Bradshaw art” remains colourful after at least 40,000 years.
Jack Pettigrew of the University of Queensland in Australia has shown that the paintings have been colonized by colorful bacteria and fungi.
These “biofilms” may explain previous difficulties in dating such rock art…