Chris Dallmann, Bielefeld University (IMAGE) Bielefeld University Caption Biologist Chris Dallmann works with stick insects, which are up to eight centimeters long. Unlike orthoptera (e.g. grasshoppers, locusts), stick insects cannot jump - they can only walk or climb. Stick insects look like small twigs, which camouflages them from predators. Credit Photo: CITEC/Bielefeld University. Usage Restrictions The image may only be used with appropriate caption or credit 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.