'Flora Unveiled' Book Cover (IMAGE) University of California - Santa Cruz Caption 'Flora Unveiled: The Discovery and Denial of Sex in Plants' offers a deep history of perceptions about plant gender and sexuality, from the Paleolithic to the 19th century. The book presents compelling evidence of a longstanding gender bias in the perception of plants as female, preventing the discovery of two sexes in plants until the late 17th century and causing the new "sexual theory" to remain controversial for another 150 years. Credit Oxford University Press 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.