Ozone depletion had a role in largest mass extinction: Study
A US-based study has added evidence to the theory that increased UV radiation due to depleting ozone contributed to the Earth's largest-ever mass extinction 252 million years ago. After a two-month simulation, researchers found pine trees became temporarily sterile when exposed to erstwhile ultraviolet radiation, 13 times more than present-day levels, which disrupted plant life and the food chain.