Flowering Plants Drove Butterfly Diversity (image) Florida Museum of Natural History Share Print E-Mail Caption As plants developed toxins, hungry caterpillars evolved ways of tolerating them. Monarchs, Danaus plexippus, co-opted the chemicals found in milkweed plants for their own defense. Credit Jeff Gage/Florida Museum Usage Restrictions Please credit Jeff Gage/Florida Museum 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.