Scales illustration (IMAGE) George Washington University Caption The missing bric-a-bracgene in some of the male orange sulphur butterfly’s wing scales gives rise to scales that reflect UV light (magenta). Where thebric-a-bracgene is present in orange sulphur females or clouded sulphurs of either sex, UV coloration is suppressed (gold). Credit Illustration by Julie Johnson/Life Science Studios Usage Restrictions With GW permission only License Original 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.