Science tells us a different story of the Iguazú Falls. About 130 million years ago, the supercontinent Gondwana broke apart. South America separated from Africa. This triggered one of the largest volcanic events in history.

At the time, the area was a giant desert. Lava poured from volcanoes, covering the desert. As it cooled and hardened, it built up layers of basalt rock.

Earth’s plates kept moving. The layers were lifted into a high plateau. Faults, or cracks, appeared in them. Water running down the faults eroded, or wore away, the land. The Paraná riverbed formed. Later, the Iguazú River appeared, feeding into it.

The falls formed at the site where these two rivers meet. Today, they are farther upstream. Erosion gets the credit. As water fell into the river from the plateau, it weathered away rock on the bottom. The upper layers crumbled.

Today, the layers of the falls look like a giant staircase. Erosion continues. The canyon gets about 3 millimeters
(0.1 inches) longer each year.

The water is just part of the beauty that surrounds Iguazú Falls. They exist in the subtropical Atlantic Forest. It is one of the most biodiverse ecosystems in South America. It is home to more than 2,000 plant species, plus mammals, birds, reptiles, and amphibians. Many of the plants and animals that live here aren’t found anywhere else in the world.

As I walked through the rainforest, I saw tall palm trees and even taller rosewoods. Papaya fruit hung from small trees under huge leaves.

Blue morpho butterflies fluttered through the air. I also caught a glimpse of a toucan in flight and monkeys in the trees. I got a good view of a young caiman. Raccoon-like coatis seemed to be everywhere! I kept an eye out for jaguars. They live here, too.