On a big day, the left reef at Teahupo’o in Tahiti is one of the world’s most spectacular waves. This uniquely intense surf zone owes much of its freakish form to an equally unique bottom contour, a ...

The feat of Polynesian wayfinding—navigating by stars, wind, and waves—had long been discounted by scholars on the grounds that ancient Polynesians didn’t have the knowledge to be master navigators.