Pilgrimage of the Monarchs

She flies from plant to plant, placing her tiny eggs carefully, each one of them alone on the underside of a milkweed. Within a few days, a head is visible as a black speck within the egg. The nearly microscopic mandibles begin to munch their way out-the only meal that isn’t milkweed for their entire caterpillar existence.

For the next two weeks, the caterpillar eats and grows, eats and grows. Each time it becomes…