Coolest Stuff blogger and adventure editor Amanda Arnold wrote about the Nazca lines recently – a collection of drawings at the ground that you can only see from the air. These geoglyphs (some are geometric shapes, while others are figures such as a monkey or an astronaut) are a mystery to this day. Why were they created? What were they for?

While we still don’t have an answer to that, we do have a clue as to what happened to the Nazca people themselves.

The Nazca civilization produced art, pyramids and beautiful textiles, along with the Nazca lines. Cahuachi, the capital for a time, may have been the biggest mud city in the world. But the Nazca had disappeared by the time the Incan Empire rose to prominence, and our answer to why they vanished may rest on a tree, the huarango tree.

This particular tree was a vital part of the desert ecosystem. It roots deeply and fixes nitrogen, which means that it prevents erosion and also enriches the soil, two important functions in this arid part of Peru. But it’s also fantastic for fuel and useful for building, which is where the conflict between the Nazca and Nature began. They cut down the trees — and then El Nino hit.

The weather event known as El Nino wreaks havoc on water and air, especially in Peru and Ecuador. The Pacific heats up, cooking the plankton in the ocean. Once the plankton are dead, the fish and birds die off, too. Heavy rains and floods drench the land.

With enough huarango cover, the Nazca would have survived. Instead, their ecosystem reached the tipping point, and everything collapsed. Without the trees, the land was vulnerable to flooding and erosion. The irrigation system failed, which meant that the crops failed, and El Nino had already killed off the fish. With the trees went the people.

And with that, I will leave you a clip of Robin Williams as a bat in “Fern Gully.” Just because I can.

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