Localization of Heart Poisons in the Monarch Butterfly

  title={Localization of Heart Poisons in the Monarch Butterfly},
  author={L. P. Brower and Samantha Glazier},
  pages={19 - 25}
The cardiac glycosides that monarch butterflies sequester from milkweed plants during the larval stage differ remarkably in their emetic potency and are concentrated to different degrees in the various parts of the body as well as in the two sexes (Fig. 1). The very high concentrations of these compounds in the wings probably facilitate learned taste rejection in predators and account for the relatively high frequency of Danaid butterflies with beak-marked wings in natural populations. The… 
Localization of Defensive Chemicals in Two Congeneric Butterflies (Euphydryas, Nymphalidae)
Examination of the distribution of sequestered iridoid glycosides in two congeneric species of nymphalid butterfly found that the pattern of localization of IGs differed between the two species.
Birds can overcome the cardenolide defence of monarch butterflies in Mexico
It is reported here that the Mexican butterflies are weakly emetic, and that taste discrimination by orioles and cardenolide insensitivity of grosbeaks allow these birds to feed freely on monarch butterflies.
Milkweed Cardenolides and Their Comparative Processing by Monarch Butterflies ( Danaus plexippus L.)
The milkweed family is known for their poisonous nature, which has found advantageous use in the preparation of arrow poisons, and also causes occasional but extensive poisoning episodes among grazing sheep and cattle in milkweed-infested rangelands.
Production of cardenolides versus sequestration of pyrrolizidine alkaloids in larvae ofOreina species (Coleoptera, Chrysomelidae)
Larvae of differentOreina species are analyzed and it is shown that the larvae contain the same defensive toxins as the adults in quantities similar to those released in the adults' secretion.
Cardenolide Intake, Sequestration, and Excretion by the Monarch Butterfly along Gradients of Plant Toxicity and Larval Ontogeny
Although it appears that large amounts of sequestration occurs in early instars, a host switching experiment revealed that caterpillars can compensate for feeding on low cardenolide host plants with substantial sequestration in the fifth instar.
Some adaptations between Danaus plexippus and its food plant, with notes on Danaus chrysippus and Euploea core (Insecta: Lepidoptera)
Behaviour of the egg-laying Monarch in captivity suggests that the concentration and quality of cardiac glycosides in the food plant are not important oviposition cues, and this butterfly can be assumed to have evolved an enzvmatic system well adjusted to the presence of cardenolides in its bodv tissues.
Cardenolide content of Danaus chrysippus butterflies from three areas of East Africa
In East Africa D. chrysippus is polymorphic and appears to act as a model in a complex mimicry ring, whereas in West Africa it is monomorphic and may have ‘shed’ most of its mimics, and this latter hypothesis is discussed in the light of the results.
Milkweeds, monarch butterflies and the ecological significance of cardenolides
SummaryThe contribution of Miriam Rothschild to the “monarch cardenolide story” is reviewed in the light of the 1914 challenge by the evolutionary biologist, E.B. Poulton for North American chemists
Differences and similarities in cardenolide contents of queen and monarch butterflies in florida and their ecological and evolutionary implications
It appears that, with respect to cardenolides, monarchs are better defended than are queens, which is unlikely to explain the apparent shift in Florida viceroy mimicry away from resemblance of the monarch, toward mimicry of the queen.
Evolutionary and ecological implications of cardenolide sequestration in the monarch butterfly
Research on monarchs has shown that monarchs sequester cardenolides most effectively, to an asymptote of approximately 350 μg/0.1 g dry butterfly, from plants with intermediateCardenolide contents rather than from those with very high or very low cardenOLide contents.


Plant poisons in a terrestrial food chain.
In the absence of complete metamorphosis in terrestrial insects, the adult food is likely to be the same as or similar to that of the nymph, with the result that the imago is not a pristine entity as far as food intake is concerned.
Variation in Cardiac Glycoside Content of Monarch Butterflies from Natural Populations in Eastern North America
The correlation between spectrophotometrically measured concentrations and emetic dose determinations supports the existence of a broad palatability spectrum in wild monarch butterflies.
Cardenolides (Heart Poisons) in a Grasshopper feeding on Milkweeds
A North African grasshopper (Poekilocerus bufonius) with warning coloration and which feeds on milkweeds, contains cardenolides similar to those found in the plant.
Cardiac glycosides (heart poisons) in the polka-dot moth Syntomeida epilais Walk. (Ctenuchidae: Lep.) with some observations on the toxic qualities of Amata (=Syntomis) phegea (L.)
The predilection shown by several Ctenuchids, and the related Arctiids, for foodplants containing cardiac glycosides or pyrrolizidine alkaloids is discussed.
Evidence for the Evolution of Unpalatability Through Kin Selection in the Heliconinae (Lepidoptera)
The evidence supports the hypothesis that genes responsible for the production of unpalatability gain their advantage in part by having individuals carrying genes identical by descent nearby, so that a predator attacking one of these individuals will learn subsequently to avoid attacking other related individuals in the same area.
Beak-Mark Frequency as an Index of Seasonal Predation Intensity on Common Butterflies
  • A. Shapiro
  • Environmental Science
    The American Naturalist
  • 1974
Despite its pitfalls, beak-mark scoring is the only method (other than direct observation) currently available for estimating the frequency of predator-prey contacts in most butterfly populations and must be interpreted with caution.
On the neuroendocrine control of ovarian development in the Monarch butterfly
The results suggest that the brain and corpora allata both act to regulate ovarian growth in this species.
The toxic actions of pyrrolizidine (senecio) alkaloids.
  • E. McLean
  • Chemistry
    Pharmacological reviews
  • 1970
The study of the effects of the alkaloids upon cell division in mammals has now reached a point where it could profitably be linked up with the more detailed knowledge of DNA metabolism in bacteria.
Why are Embryos so Tasty?
The prevalence of intense predation on eggs suggests that predators are important selective agents for egg characteristics.