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The animal on the cover of Learning Oracle PL/SQL is a zebra butterfly, also known as a zebra longwing. The zebra butterfly is named for its long, narrow wings that have zebra-like yellow stripes. It has a thin abdomen and long black antennae. In caterpillar form, the zebra butterfly has a white body with long black spines and a yellow head. When zebra butterflies are caterpillars, they feed on the leaves of passion flowers, which contain toxins that make the butterflies poisonous and unpleasant tasting to predators.
Native to tropical climates, including the southern U.S. from Texas to Florida, heliconius charitonius is perhaps the most intelligent butterfly and leads a surprisingly social life. Zebra longwings roost in flocks with their kin, returning to the same perch every night, and giving first choice of perches to their elders. The butterflies sleep so soundly that you could pick them up, until th efirst light of day, when the first on up wakes the others with a gentle touch.
Adults live on flower nectar and pollen and are especially fond of lantana and shepherd's needle. The female lays her eggs on the passion vine, which will serve as food when the pupae emerge as caterpillars. The total life span of a zebra longwing ...