Dr. Valentina Mella with Koala (image) University of Sydney Share Print E-Mail Caption Dr. Valentina Mella with koala in Gunnedah, NSW, Australia. Credit University of Sydney Usage Restrictions For this story only. 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.