Orangutans (2 of 2) (IMAGE) University of Zurich Caption This image shows examples of the daily travel routes of the orangutans observed. The green arrows show spontaneous long calls, while the red arrows mark response calls to the noises emitted by other males. Credit Picture: UZH Usage Restrictions None 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.