Smoking Gun of Permian Extinction (2 of 3) (image) University of Calgary Share Print E-Mail Caption The coal‑ash particle on the left is from the latest Permian extinction boundary at Buchanan Lake. Nunavut, the particle on the right is from a modern power plant. Credit Hamed Sanei, NRCan/University of Calgary Usage Restrictions With credit Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.