One monarch butterfly flies by. Then another, and they fly, the butterflies seem to float in the sky. They make beautiful shadows on the ground below. They seem to be In fact, there are so many butterflies that the groups look like beehives wh every trees. And when they fly, the sound of 150 million in create a soft sound, as though it is raining. People say Mexico is the only place world where you can hear the sound of butterflies wings moving. The Migration year, mill and millions of monarch butterflies migrate from the U.S.A. and Canada. They go to a place high in the mountains of Mexico. There, they can escape from North America's winter To get there, the monarchs often travel over 80 kilometers a day. But what's really amazing is that the butterflies make the trip only once. Somehow they know exactly where to go. The Effect on People,5 After the butterflies arrive in Mexico, people gather to watch. The effect on people is amazing. Young and old, men and women, locals and people from far away-everyone is smiling and friendly. It's as though the butterflies encourage people to be their best.