The boat docks in a tiny harbor at the base of a cliff on East Anacapa Island, off the coast of Southern California. I climb a switchback metal stairway bolted to the side of the cliff like a shelf — 157 grated stairs, through which I can see the rocking water of the cove below. The island is sun drenched in the middle of September, and there is no shade anywhere. A glittering heap of ancient seashell fragments scatters light: the casual litter of the Chumash, who came here five thousand years ago. They crossed the channel in rough dugout canoes, then hopped from island to island across the violent, foaming seas between. The island’s name comes from the Chumash word anyapakh, for “mirage.” A dozen miles away, across the wide channel, the mainland slides behind the haze.