Every year, monarch butterflies travel thousands of miles from their summer homes in northern states and Canada to wintering spots in Mexico and southern California. In spring, they make the journey back again. However, the butterflies die before they reach their northern homes. New butterflies, hatched from eggs laid by migrating monarchs, complete the journey. A scientist wanted to know how the new butterflies found their way to their northern homes if they had never been there before. Which of the following is not a testable hypothesis about monarch migratory behavior? (SC.912.N.1.1)
Monarchs can sense Earth’s magnetic field.
Monarchs are prettier than other types of butterflies.
Monarchs follow routes that have many milkweed plants.
Monarchs can smell the remains of the last season’s dead monarchs.