This is a very interesting article from the New York Times about how bee species give a clue to how early North and South America were joined by a land bridge (it’s earlier than geologists thought).
Bees Migration Holds Clues to Geologic History
Two new bee species shed light on Panama’s history as a land bridge
between South and Central America, scientists are reporting.
By SINDYA N. BHANOO
Published: October 24, 2011