The well-known Lascaux paintings, founded by some teenagers while playing in the cave located in France. At the beginning of the discovery of the cave painting, 1800 visits were allowed to visit the cave per day. However, due to the large quantity of people visiting the cave, more carbon dioxide exhaled is affecting the cave painting, which was estimated to be 15000 years old.
The emitting of carbon dioxide caused the appearance of lichen and on the walls, some small crystals. The preservation is blamed for that. Since than, a replica was made to attract tourists to come and have a look, and it attracts more than 250 thousands of tourists visiting. However, only 5 people each day, and five days per week, have people been allowed to visit the real cave. Hence, new problems have emerged in 2001 when a white mould was found, spreading across the cave painting. But now, the painting is found to be having black stains on it; and the area and number of them is increasing.
The most possible thing that induced this to happen is that, the temperature has risen from 12 to 12.5 and that changes the initial temperature surrounding the cave painting. Global warming is certainly the main cause for this to happen.