Northern cardinal. (IMAGE) University of Helsinki Caption As the environment warms, southern species such as the grass wren and the northern cardinal spread further north in search of a suitable climate. Credit Aleksi Lehikoinen. Usage Restrictions Credit to Aleksi Lehikoinen, University of Helsinki. License Original 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.