Widening the Panama Canal and the colliding continents

The Panama Canal, begun in 1904 and finished in 1914, is a 48 mile ship canal in Panama that joins the Atlantic Ocean and the Pacific Ocean and is a key conduit for international maritime trade. Annual traffic has risen from about 1,000 ships in the canal’s early days to 14,702 vessels in 2008. One of the largest and most difficult engineering projects ever undertaken, the canal had an enormous impact on shipping between the two oceans, replacing the long and treacherous route via the Drake Passage and Cape Horn at the southernmost tip of South America. A ship sailing from New York to San Francisco via the canal travels 5,900 miles, well under half the 14,000 mile route around Cape Horn.

Three million years ago, the Americas collided. The creation of the Panama Isthmus – the narrow land bridge that joins the two continents – wreaked havoc on land, sea and air. It triggered extinctions, diverted ocean currents and transformed climate.

Now a multi-billion dollar project to widen the Panama Canal for the first time in it’s history is set to reveal new secrets about the event that changed the world. Authorities hope that this will increase revenue from shipping. However, the massive excavations have also proved to be a “gold mine” for scientists, trying to uncover Panama’s hidden past.

Dr Camilo Montes, a geologist at the Smithsonian Tropical Research Institute (STRI) in Panama, explained: “What this represents is a once-in-a-century chance to find out what really happened when the Americas collided”.

As entire hillsides are being blasted away to expand the canal, amazing fossils are emerging that shed light on this key event. However, scientists only have a short window to collect the fossils before they are re-buried beneath concrete.

“Basically what we are doing is a rescue effort”, said Dr Carlos Jaramillo, another geologist at STRI. “It’s a race against time. When a new fossil site is discovered we have two, maybe three months. That’s all!”

“We work all day, every day, in the canal. Whether there is blazing sun or pouring rain, we always have a team out searching for the fossils.”

What is being found helps us better understand an extraordinary event that scientists call the “Great American Interchange”.

Dr Bruce MacFadden, an expert on fossil mammals at the University of Florida, US, explained: “When the Americas collided about three million years, it caused of a kind of land rush”.

“Animals that were native to North America – sabre-toothed cats, horses, camels and elephants – surged south across the land bridge. Animals from South America such as giant sloths and armadillos, moved north”.

In an ecological experiment on a scale never before seen, the animals of two continents freely mixed. Unable to compete with the waves of invaders, some species on both continents went extinct.

The event helped shape the ecology of the Americas to this day. READ MORE