This video is about monarch butterfly migration.
From Science News:
Monarch butterflies’ ancestors migrated
The insects originated in North America, genetics study finds
BY Kate Baggaley
5:06pm, October 1, 2014
The earliest monarch butterflies arose in North America and were migratory, contrary to what scientists believed. Over time, the butterflies evolved populations in other locations, some of which stay put year-round, scientists conclude October 1 in Nature.
Because many of the monarch’s closest butterfly relatives live in the tropics and do not migrate, “the thought was that the butterflies [came] from South and Central America and became migratory from resident populations,” says Tyler Flockhart, a conservation biologist who concentrates on monarchs at the University of Guelph in Canada. “But that doesn’t seem to be the case.”