Feather Detail (IMAGE) Smithsonian Caption This scanning electron photomicrograph shows the prongs on the downy barbules of an Apteribis sp. feather. Credit Carla Dove 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.