Localization of Heart Poisons in the Monarch Butterfly

@article{Brower1975LocalizationOH,
  title={Localization of Heart Poisons in the Monarch Butterfly},
  author={L. P. Brower and Samantha Glazier},
  journal={Science},
  year={1975},
  volume={188},
  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)
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TLDR
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TLDR
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TLDR
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TLDR
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Cardenolide content of Danaus chrysippus butterflies from three areas of East Africa
TLDR
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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
TLDR
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
TLDR
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.
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