It was a swamp denizen and a fearsome predator, able to eat any animal that caught its eye. This giant serpent looked something like a modern-day boa constrictor, but behaved more like today’s water-dwelling anaconda. The lord of this jungle was a truly spectacular creature-a snake more than 40 feet long and weighing more than a ton. And there were seven-foot-long lungfish, two to three times the size of their modern Amazon cousins. The river basin held turtles with shells twice the size of manhole covers and crocodile kin-at least three different species-more than a dozen feet long. Mud from the flood plain periodically coated, covered and compressed the dead leaves, branches and animal carcasses in steaming layers of decomposing muck dozens of feet thick. Deep water from north-flowing rivers swirled around stands of palm trees, hardwoods, occasional hummocks of earth and decaying vegetation. Mean temperatures may have hovered in the mid- to high-80s Fahrenheit or higher.

The trees had wider leaves, indicating greater precipitation-more than 150 inches of rain per year, compared with 80 inches for the Amazon now. We have it all, and you can’t find it anywhere else in the tropics.”įifty-eight million years ago, a few million years after the fall of the dinosaurs, Cerrejón was an immense, swampy jungle where everything was hotter, wetter and bigger than it is today.

“Cerrejón is the best, and probably the only, window on a complete ancient tropical ecosystem anywhere in the world,” said Carlos Jaramillo, a paleontologist at the Smithsonian Tropical Research Institute. The multinational corporation that runs the mine, Carbones del Cerrejón Limited, extracted 31.5 million tons of coal last year alone.Ĭerrejón also happens to be one of the world’s richest, most important fossil deposits, providing scientists with a unique snapshot of the geological moment when the dinosaurs had just disappeared and a new environment was emerging. It is one of the world’s largest coal operations, covering an area larger than Washington, D.C. In the lowland tropics of northern Colombia, 60 miles from the Caribbean coast, Cerrejón is an empty, forbidding, seemingly endless horizon of dusty outback, stripped of vegetation and crisscrossed with dirt roads that lead to enormous pits 15 miles in circumference.

Largest anaconda ever recorded