The Queen is an interesting butterfly because its survival tactic is to mimic the poisonous Monarch butterfly.

Monarch caterpillars eat milkweed leaves which contain a toxin. The caterpillars store the toxin which then passes on to the adult. Any bird that tries to eat a Monarch is left with a bad taste in its mouth and learns to leave the species alone. The similar-looking but non-poisonous Queen butterfly then benefits from the same treatment.