CORRECTS BYLINE TO DAVID LONGSTREATH NOT DAVID LONGSTREET FILE - In a May 5, 1986 file photo, Dr. Clyde Snow holds a human skull in his office in Oklahoma City, Okla. Snow, a forensic anthropologist who worked on cases ranging from the assassination of President John F. Kennedy to mass graves in Argentina, died Friday, May 16, 2014, at Norman Regional Hospital in Norman, Oklahoma,, says his wife, Jerry Snow. He was 86. (AP Photo/David Longstreath)