Recent connection between North and South America reaffirmed

Long ago, one great ocean flowed between North and South America. When the Isthmus of Panama joined the continents, it also separated the Atlantic from the Pacific Ocean. If this took place much earlier than the accepted date of 3 million years ago as recently asserted by some, the implications for both land and sea life would be revolutionary. A new paper firmly set the date at 2.8 million years ago.