They've existed for thousands of years but it's the lowly fungus that could finally be the death of France's most famous prehistoric cave paintings. Invading gray and black mold is threatening the animal images in the Lascaux cave in southwestern France, and scientists are uncertain what has caused it. The government has approved treatment with a fungicide and the cave will be sealed for up to four months, reports the New York Times.
The images of horses, bulls, stags, ibexes and oxen are believed to be 17,000 years old. It's the second time in a decade the paintings have been threatened by mold that may currently be caused by climate change, lights or carbon dioxide exhaled by visitors. The cave has been closed to the public since 1963 and tourists must visit a replica cave, which draws 250,000 people a year.