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Biology

Seasonal Migration Patterns and Navigation in Monarch Butterflies

Quick fact

Monarchs that migrate in autumn are several generations removed from those that left in spring, yet they navigate to the exact same overwintering sites in Mexico—a feat guided primarily by an internal sun compass that adjusts for the time of day.

Why this is interesting

Every autumn, millions of butterflies that have never made the journey begin a 4,000-kilometer flight to mountains they have never seen. How do they find their way?