KAMPONG PHLUK — The water around our boat is so opaque with yellow clay that I worry my hand will vanish if I dip it in. The boat itself is made of wooden planks sealed with resin, driven by an engine that looks like nothing I have ever seen, a propeller trailing far behind the stern on a rickety metal frame. Our pilot is 13, or might be, but I can’t really ask him over the noise.

But none of this is the interesting part. The interesting part, the reason we endured the hourlong scooter ride and all the dirt roads to get here, is rolling past us on the banks of this river, where the life of a village is unfolding 20 feet above our heads.