New Scientist
Image: Kristen Grace
The monkeys started it. About 3 million years ago, one of the most epic ecological struggles of all time – between the animals of North and South America – was at its peak.
Now a fossil from Panama suggests the opening salvo actually came some 18 million years earlier, courtesy of a monkey invader.
The appearance of the Panama isthmus, generally dated to about 3 million years ago, provided a land connection between North and South America for the first time. Once it formed, animals from the north – including sabre-toothed cats, deer and horses – surged south, as southern species – such as terror birds, ground sloths and armadillos – pushed north.
The ecological battles, dubbed the Great American Interchange, raged for generations. Many species were lost.
Now it seems that the first animal to cross continents did so long before the isthmus emerged.
Jonathan Bloch at the University of Florida, Gainesville, and his colleagues have been studying 21-million-year-old sediments in Panama that were deposited on the North American side before the isthmus formed. They found seven teeth belonging to a South American monkey. Read more on newscientist.com…
