Nectar Humidity Plume (image) University of Arizona Caption This is an evening primrose flower as it appears to the human eye (left) and to a hawkmoth (right). if nectar is present, an invisible plume of humidity emanates from the flower, telling the moth if it warrants a visit. Credit Martin von Arx Usage Restrictions This visual may only be used in conjunction with reporting/posting of this news release. Image/video credit must be included exactly as indicated. 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.