Scientists in India have discovered a remarkable explanation for the phenomenal longevity of the cave paintings at Ellora in Maharashtra, which were painted onto clay plaster more than 1500 years ago.

The Buddhist, Hindu and Jain artists who produced the frescoes mixed marijuana into their plaster, creating a natural deterrent to insects. Studies have discovered that the Ellora plaster is made up of nearly 10% Cannabis sativa, whose active ingredient, THC - the chemical responsible for marijuana’s narcotic effects - is an effective pesticide, deterring insects and other parasites. The famous cave paintings at nearby Ajanta were made with marijuana-free plaster, and more than 25% of the paintings have severe insect damage.
Read more: timesofindia.indiatimes.com