Ron Harper, who starred on Planet of the Apes and four other short-lived primetime series and on the final season of the beloved kids TV show Land of the Lost during a very busy 15 years on television, has died. He was 91.

Harper died Thursday of natural causes at his home in West Hills, his daughter, Nicole Longeuay, told The Hollywood Reporter.

After understudying for Paul Newman on Broadway, Harper portrayed Det. Bert Kling alongside Norman Fell, Robert Lansing, Gregory Walcott and Gena Rowlands on the 1961-62 NBC cop show 87th Precinct, based on the novels of Ed McBain. He played Jeff Conway, the husband of Connie Stevens character, on the 1964-65 ABC sitcom Wendy and Me, also starring George Burns, who produced the show and appeared as the owner of the apartment building in which the young couple lives.

Next up for Harper were turns as the son of Jean Arthurs lawyer they both portrayed lawyers, in fact on CBS The Jean Arthur Show in 1966 and Lt. Craig Garrison on the World War II-set Garrisons Gorillas, which aired on ABC in 1967-68.

All four never made it to a second season, with 87th Precinct lasting 30 episodes, Wendy and Me 34, The Jean Arthur Show 12 and Garrisons Gorillas 26.

In 1974, Harper finally seemed to have a hit on his hands when he landed the role of astronaut Alan Virdon on CBS Planet of the Apes. The series, after all, had come on the heels of the five Planet of the Apes movies and starred Roddy McDowall, who was in four of the films, as a chimpanzee.

However, the high-cost show, which also starred Jim Naughton as an astronaut, performed poorly in its Friday night slot and was canceled, with just 14 episodes airing.

Ron Harper (right) and James Naughton on Planet of the Apes 20th Century Fox Film Corp./Courtesy Everett Collection Our Planet of the Apes stories degenerated into The Fugitive with fur. I think thats one of the things that curtailed what should have been a longer run, Harper said in an interview for Tom Weavers 2008 book, I Talked With a Zombie.

Harper then joined Sid and Marty Kroffts Land of the Lost in 1976 for its third and final season, stepping in for Spencer Milligan to play the familys Uncle Jack on the NBC sci-fi show. He was on just 13 episodes, but those showed up often in repeats over the years.

The stories were very good, Harper said in 2005. Each generation of children as they come up and are exposed to it like those stories and remember them, pass them right on. I have about three tapes, and Ive been showing them to my daughter since she was 5. And she still, of all my series, loves Land of the Lost best.

Ron Harper with Kathy Coleman on Land of the Lost Courtesy Everett Collection Ronald Robert Harper was born on Jan. 12, 1933, in Turtle Creek, Pennsylvania, outside Pittsburgh. He graduated from Turtle Creek High School and earned a scholarship to Princeton University, where he did two seasons of summer stock. He then was offered a fellowship to Harvard Law School.

I kept saying to myself, Should you waste your good education being an actor? And that little voice within me kept saying things like, What do you want to take that fellowship to Harvard Law for? Be an actor. Starving is fun, he said in 1966. And like the fool that any actor has to be, I listened to that dumb little voice.

He studied with Lee Strasberg, served in the U.S. Navy and in 1959-60 was Newmans understudy in Tennessee Williams Sweet Bird of Youth, directed by Elia Kazan. He got to play opposite Geraldine Page four times one week when Newman was ill.

In my last performance of it, I saw Paul in the audience, he recalled in 2015. If he was not feeling too well, he was feeling a little bit better. He was a wonderful, sweet guy. I think he probably felt generous enough to say, Let Ron do one or two of the performances.

After that, he appeared on installments of such shows as Tales of Wells Fargo, Thriller, Wagon Train and The Tall Man before landing on 87th Precinct.

Ron Harper and Connie Stevens on Wendy and Me Courtesy Everett Collection Harper returned to Broadway in 1972 in 6 Rms Riv Vu and did lots of soap operas, among them Another World, Loving, Capitol, Generations, Where the Heart Is and Love of Life.

His rsum also included the movies The Wild Season (1971), The Odd Couple II (1998) and Pearl Harbor (2001) and TV guest stints on The Big Valley, Remington Steele, Beverly Hills, 90210, Melrose Place, Walker, Texas Ranger, The West Wing and Cold Case.

In addition to his daughter, survivors include his son-in-law, Daniel; granddaughters Ronnie and Harper; and ex-wife Shirley. His first wife was actress Sally Stark.