A butterfly in the Amazon rain forest flutters its wings. The air stirs and a small whisper of air moves past the ferns, gathering moisture from the fronds. With the heat of the day, this moist breeze builds and rises through the canopy, escaping into the waiting blue of the sky above where it condenses, forming a small cloud. This wisp of cloud moves along gathering more moisture, growing into a thunderous mass of cumulus wrath. Several miles away, a tribal chief examines the sky and knows that rain is coming. The deluge lasts for hours. What is not washed away is soaked through and through. The ground is waterlogged. The few seeds that were planted in the family’s plot have begun to push up through the soil, and this water will bring them further along. In a few weeks, the plants will be in bloom—a place to feed and rest for a passing butterfly. The family will have a good harvest this year.