Hummingbird in Flight (IMAGE) U.S. National Science Foundation Caption When males perform courtship dives for females, neighboring fluttering tale feathers produce interaction frequencies. In some species, for or five species may interact with one another to produce sounds. Credit Anand Varma, www.varmaphoto.com Usage Restrictions Special Restrictions: Use of this image is restricted to educational use only and must include credit to the author, Anand Varma. For any other use of this image, permission must be granted by the owner at aavarma@gmail.com www.varmaphoto.com 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.