© Bruce D. Taubert

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Royal Pain

By Amanda Fruzynski

Queen Elizabeth I fought off predators (would-be suitors) so that she could wear the crown herself. The queen in a game of chess devastates opponents with superpowers that only she possesses. And the Queen butterfly, a member of the milkweed-eating family of fluttering insects, keeps predators at bay with her own set of defense mechanisms.

In most cases, insects avoid milkweeds because the milky insides of the plants will often glue a predator's mouth shut, and the plants' poisons will turn away those intruders that get past the sticky latex. But, according to Ron Rutowski, an Arizona State University biology professor, Queen caterpillars have developed a system of biting the plants so that the "milk" drains out, thus allowing the insects to consume the plants and store their poisons into adulthood. As a result, Queen caterpillars, which are white with yellow spots and black stripes and three pairs of black prongs, emerge from their cocoons with a built-in defense to fend off predators.

When birds and other animals try to eat the adult Queens, they experience a putrid taste that sometimes leads to vomiting. That experience isn't soon forgotten, and Queen butterflies are typically left to flutter safely throughout the southernmost parts of the United States. But there's more to a Queen butterfly than its ability to outsmart milkweed plants and predators, and it's related to reproduction.

The only difference between males and females is a small brown circle on each of the lower wings of the males. Those circles come into play during the species' intricate mating dance. According to Rutowski, that courtship is perhaps the most unique thing about Queen butterflies. The males, he says, must ingest alkaloids from certain plants, and then transfer those alkaloids to females from tiny hairs in the brown circles.

Although you may never witness this unique courtship, Queen butterflies are common in Arizona. According to Adriane Grimaldi of the Central Arizona Butterfly Association, they can be found near gardens year-round — adults gather nourishment from verbena and lantana plants — but their numbers decrease in the coldest months of winter, and Queens tend to avoid the midday heat in the summer. They're around, but don't get too attached to any one butterfly. After royally outsmarting predators, Queens live for only one or two months as adults.

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