Lichen Attack: 5,000-Year-Old Rock Art Is Deadly Threatened

One of the slowest art thefts in history is currently taking place in the Negev Desert, where a host of hardy fungi and lichens are destroying ancient works of art before our eyes. Petroglyphs carved by ancient people have survived for 5,000 years, but now they are at risk of being lost forever.

The desert is located in southern Israel, where you can find rocks marked with petroglyphs of ibex, goats, horses, donkeys, camels and strange abstract forms. If this is the first you’ve heard of petroglyphs, they are defined as prehistoric rock carvings – in this case, created by hunters, herders and traders who roamed the Negev since at least the third millennium BCE.

The petroglyphs have survived for thousands of years, but a new study has shown that several species living on these rocks could pose a monumental problem. Sampling of the rock surfaces showed that they support a relatively low diversity of species compared to the surrounding soil, but the species that are present are known to be destructive.

The list of culprits includes many species of fungi. Alternaria, Cladosporium, Coniosporium, Vermiconidia, Knufia, PhaeothecaAND Devriesia genera, as revealed by DNA barcoding and direct sequencing. All of them are microcolonial fungi, other than Alternaria AND Cladosporiuma group famous for setting up camp in desert environments. They are also known to be bad when it comes to rock art.

“Microcolonial fungi are considered highly dangerous to stone artifacts,” first author Laura Rabbachin, a doctoral candidate at the Academy of Fine Arts in Vienna, Austria, said in a statement. “For example, they have been identified as a probable cause of the deterioration of stone cultural heritage in the Mediterranean region. Lichens are also well known to cause rock deterioration and therefore pose a potential threat to stone cultural heritage.”

We may have managed to point the finger at the microbial saboteurs, but unfortunately, identifying the problem has not brought us any closer to a solution.

“These natural weathering processes cannot be stopped, but their weathering rate largely depends on whether and how the climate changes in the future,” added senior author of the study and Rabbachin’s supervisor, Prof. Katja Sterflinger. “We can monitor the microbial communities over time and, most importantly, document these valuable works of art in detail.”

I think we have our sketchbooks ready.

The study results were published in the journal Frontiers In Fungal Biology.