“Five centuries ago, when the Europeans first came knocking, more than ten million Indians lived in the rain forest,” Ernesto tells me. “Today there are fewer than two hundred thousand. Each time a tribe disappears, we lose all the knowledge they have accumulated about the plants and the animals.” He pauses as our plane turns sharply and begins to descend. “So the problem is not that the shadow of man is falling over the rain forest,” he whispers. “Men have lived there for centuries.” The dozing guard, sensing our descent, starts to shift and blink. Ernesto finishes quickly: “The problem is that the wrong men are coming now, for the wrong reasons. Soon it will be gone.”

Our plane is now almost at tree level. I look down and see a gleaming river, and two large trucks waiting by its muddy bank.

It seems like we will fly right into the tree canopy, but at the last minute it parts and the Cessna—with its engine hiccuping wildly—touches down on the river. It skids to a stop near the trucks.

Ten minutes later I find myself in the back of an old flatbed truck, rumbling along on a logging trail. This is not the swampy rain forest that Gisco and I found when we were shot down in our balloon. This is nearly impenetrable dry-floored jungle, exploding in all directions with an improbable amount of life, like a child’s kaleidoscope constantly turning to new and incredible patterns.

Towering trees piggyback over each other in a centuries-old wrestling match, straining toward the precious sunlight that is almost completely blocked out from our low vantage point. From the canopy, high above, vines dangle down hundreds of feet till their tendrils brush flowers with brilliant petals.

“It’s unbelievable,” I whisper to Ernesto as we cling to handholds. The truck bounces along over rocks and crashes through low branches that have grown across the path. “The variety of life here … and the intensity of it … is just …” I stop, at a loss for words. “Shocking.”

He nods and rewards me with a little smile. “Would you believe that this planet is four and a half billion years old and there are more different species right here in the Amazon than have ever existed anywhere else, at any time, in that whole time span? Or that there are more species of fish in one Amazon lake than in the Atlantic?”

“I believe it,” I whisper. “I see it all around me.”

“No you don’t,” he corrects me. He pauses and seems to be listening and smelling and almost drinking the forest in as we crash through it on our big truck. “Most of it you can’t see.” His tone changes and his words become almost poetic. “The sloths high above us that live their whole lives in the trees, hanging upside down, so that the organs of their bodies are in different places than the organs of other mammals.”