fiels study (IMAGE) University of Zurich Caption The researcher performing an acoustic playback experiment on a great spotted woodpecker. The loudspeaker is attached on a branch. Credit (Picture: Alain Blanc , ENES team) 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.