Cowbirds and Warblers (image) University of Illinois at Urbana-Champaign Share Print E-Mail Caption Researchers observed the results when female cowbirds, left, laid their eggs in the nests of prothonotary warblers, right. Credit Photos by Chris Young (cowbird) and Michael Jeffords (warbler) Usage Restrictions Image may be used only to accompany stories about the research described in this release. Credit required: Photos by Chris Young (cowbird) and Michael Jeffords (warbler) Share Print E-Mail 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.