#Id: 9731
                                                        #Unit 6. System Physiology – Plant
                                                        The specialist caterpillars of the monarch butterfly
(Danaus plexippus) are insensitive to the terpenoid toxins. They feed on milkweed leaves and retain the cardenolides. As a result, most insectivorous birds quickly learn to avoid eating monarch caterpillars and adult monarch butterflies.