Zebra Finch (IMAGE) University of Utah Caption University of Utah scientists studied the colorful zebra finch to learn more about the factors that allow the songbirds to sing over a wide range of frequencies while females utter only brief lower-frequency calls. They found that the males' more powerful vocal muscles were much more important than the pressure of air within the lungs. Credit Nataliia Verzhbitskiy, University of Utah. 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.