Finch Pulling Cotton from Dispenser (image) University of Utah Caption A finch in Ecuador's Galapagos Islands pulls a cotton ball from a dispenser set out by scientists. A University of Utah study showed that when the cotton is treated with permethrin -- a mild pesticide used in human head-louse shampoo -- and the birds use the cotton in their nests, blood-sucking fly maggots are killed, thereby protecting the finches and their offspring that often fall prey to the maggots. Credit Sarah Knutie, University of Utah Usage Restrictions None 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.