Migrating birds are excellent navigators, hitting small oceanic islands like radio-guided airplanes. But some of them seem to cross unnecessary oceans. The Arctic tern, for instance, nests in summer in North America; when winter approaches, it heads for Antarctic regions near South America. But instead of flying south, the most direct route, it heads eastward across the North Atlantic to Europe, then down the African coast and across the South Atlantic. Other birds that migrate long distances take similar detours. All this tends to vex and confuse the ornithologists, who want to know why birds behave that way.
In !ast week's Science...
To continue reading:
or
Log-In
