Solved with barnacles
ACADEMICS believe they have discovered the key to finding missing people lost at sea. Marine scientists at UNSW used a common barnacle to develop two equations that can help estimate when and where a boat may have sunk. They looked at lepas, a genus of goose barnacles, because they only attach to floating objects like boats. For instance, if a boat vanished in an unknown location and its debris washes up on shore weeks later, scientists can measure the barnacle count to determine how long the debris drifted.