Monkeys resembling today's capuchins accomplished the astonishing feat of crossing at least 100 miles (160 km) of open ocean 21 million years ago to get from South America to North America eons before the two continents joined together.
Scientists said on Wednesday they reached that conclusion based on the discovery of seven little teeth during excavations involving the Panama Canal's expansion, showing monkeys had reached the North American continent far earlier than previously known.
The teeth belonged to Panamacebus transitus, a previously unknown medium-size monkey species. South America at the time was secluded from other continents, with a strange array of mammals evolving in what 20th century American paleontologist George Gaylord Simpson called "splendid isolation."