An orange and black insect famous for one of the longest…

An orange and black insect famous for one of the longest migrations in the animal world. Each autumn, millions fly from Canada and the United States to overwintering sites in the mountain forests of central Mexico, covering huge distances. No individual completes the round trip, which spans several generations. Its caterpillars feed on milkweed, absorbing toxins that make the adults distasteful to birds, their bright colours acting as a warning.

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