Pernell Elvin Roberts, Jr. (May 18, 1928 – January 24, 2010) was an American stage, movie and television actor as well as singer. In addition to guest starring in over 60 television series, he was widely known for his roles as Ben Cartwrights eldest son, Adam Cartwright, on the western (Western (genre)) series (television series) Bonanza (Bonanza (TV series)), a role he played from 1959 to 1965 — and as chief surgeon Dr. John McIntyre, the title character on Trapper John, M.D. (1979-1986).cite news title="Bonanza" Star Pernell Roberts Dies At 81 first=Alex last=Dobuzinskis agency=Reuters url= work=New York Times date=January 25, 2010 accessdate=2010-01-26

He was also widely known for his life-long activism (social justice), which included participation in the Selma to Montgomery marches in 1965 and pressuring NBC to refrain from hiring white (Caucasian race)s to portray minority characters.