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Biology

Chemical Defense and Sequestration of Toxins in Monarch Caterpillars

Quick fact

Monarch caterpillars gather and store poisonous compounds called cardiac glycosides from milkweed plants, making them taste so bad that birds learn to avoid them after a single attempt.

Why this is interesting

A monarch caterpillar munches on a milkweed leaf that would sicken most animals. How does it turn this toxic meal into a shield?