Southern Arizona Sky Island (IMAGE) University of Arizona Caption Oak trees in the northern Santa Rita Mountains, one of southern Arizona's "sky island" habitats. Oak trees were one of the plant groups included in the study. Credit John J. Wiens Usage Restrictions This visual may only be used for the purpose of posting and/or reporting of this news release. Credit information must be provided as indicated. 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.