Arizona native David Warner was used to traveling over great distances of water serving America as a petty officer aboard the aircraft supercarrier USS Independence (CV-62) in the 1970s. But his most demanding and daring mission was being captain of his own 50-foot boat, the Nova Esperanza,  traveling up the Amazon  “about a week” upriver from the last major outpost of civilization, Manaus, Brazil. “There was no way to tell how many miles that was,” David Warner said, “but if you travelled downriver for a few days, you’d reach Manaus. That’s how distances are measured there. If you got sick up river, or had a bad accident, you were on your own.” Nothing he learned in the Navy, he said, prepared him for what he would do, see and feel in the 12 years he lived on the river—from 1985 to 1997—with his young California wife and his two children born …