SAN CLEMENTE ISLAND, CALIFORNIA—A prehistoric boat effigy carved from brittle submarine volcano lava has been discovered on the surface of an archaeological site on San Clemente Island, which is owned and operated by the U.S. Navy for training programs. The effigy represents the type of boat used by California Indians in the sixteenth century. “Boat effigies like the one found are exceedingly rare in the archaeological record. …This is something someone made representing a high skill level,” said Andy Yatsko of the Naval Facilities Engineering Command Southwest in San Diego.