Timeline of Discovery (IMAGE) University of East Anglia Caption Documents dating back to the 16th Century provide a unique insight into one of Darwin's landmark studies -- according to University of East Anglia research. In 1862, Darwin presented the case that some plant species have two floral forms. But Darwin was not the first to observe "heterostyly." It had in fact been documented in 16th, 17th and 18th Century botanical records. Credit University of East Anglia 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.