Here is paradise, a place of pink dolphins and molten sun that drips from the sky, gilding as it goes the clouds, the rainforest canopy, the black waters of Hatum Posa Lake and the brown-skinned children gliding along its surface. As we entered this lake from Ucayali River – high in the Peruvian reaches of the Amazon – the children hastened down the steep banks from their village, climbed into a fleet of wooden dugouts and rowed out to meet us. We’d been delivered into this National Geographic wonderland by Aqua Expeditions, and had cruised with them through the churning birthplace of the mighty Amazon River. Now the children gather around our boat and invite us into theirs’. A young girl rows me around the lake, its inky liquid slapping rhythmically against the low-slung hull. The air fills with the cry of macaws and tinamous from the thermals high above us, the cackling of squirrel monkeys and the laughter of the children as they balance on the razor-thin rims of their canoes and jump into the gold-skinned waters of Hatum Posa Lake.