A View of the Rockshelter at Magubike (IMAGE) University of Alberta Caption This 2012 image shows the structure used by inhabitants of the region for well over 200000 years. Credit Pamela Willoughby, University of Alberta Usage Restrictions None License Licensed content 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.