Surveying for Alien Vertebrates (IMAGE) University of Adelaide Caption Pablo García-Díaz, lead author, is surveying for alien vertebrates in the rain forest of Christmas Island. Credit Photo: Pablo García-Díaz Usage Restrictions For use with this story 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.