A particular set of rock paintings dating from more than 40,000 years ago don't seem to be made of paint anymore. According to a new study published in the journal Antiquity, the vibrant artworks were long ago colonized by colorful microbes, which serve as "living pigments" in the paintings. Lead researcher Jack Pettigrew, of the University of Queensland in Australia, explains:
"'Living pigments' is a metaphorical device to refer to the fact that the pigments of the original paint have been replaced by pigmented micro-organisms.... These organisms are alive and could have replenished themselves over endless millennia to explain the freshness of the paintings' appearance." [BBC News]
When the researchers analyzed the so-called Bradshaw rock artworks found in Western Australia's Kimberley region, they didn't find paint. Instead they found a black fungus, probably belonging to a fungi group known as Chaetothyriales, as well as a reddish organism that is suspected ...
