Academic Reading
The monarch butterfly's journey
AEach year, monarch butterflies in North America make an astonishing migration, travelling thousands of kilometres from Canada and the northern United States to spend the winter in the forests of central Mexico. What makes the journey remarkable is that no single butterfly completes the round trip.
BInstead, the migration is spread across several generations. The butterflies that fly south are the great-grandchildren of those that flew south the previous year, yet somehow they find their way to the very same forests, guided by instinct alone. How they do this is still not fully understood.