Ron Harper, “Land of the Lost” and “Planet of the Apes” Star, Dead at 91

"He laid his head down to rest and never woke up again," his daughter Nicole Longeuay wrote of the late actor's passing on social media

Ron Harper, best known for his roles in Land of the Lost and Planet of the Apes, has died. He was 91.

His daughter, Nicole Longeuay, confirmed that the late actor died of natural causes in his home in West Hills, California on Thursday, per The Hollywood Reporter.

"It's with a heavy heart that I must share the news of my father's passing... He laid his head down to rest and never woke up again," Longeuay wrote in a social media post captured by Extra. "Although it was not public knowledge, Alzheimer's Dementia started to take his mind from him years ago, it's hard to believe he is physically gone now too."

"I know he'll be watching over all of us, until we meet again," she concluded.

PEOPLE has reached out to Harper's rep for comment.

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Born on Jan. 12, 1933, in Turtle Creek, Pennsylvania, Harper graduated high school and attended Princeton University with a scholarship. Following his graduation, he was then awarded a fellowship at Harvard Law School, which he turned down to pursue a career in acting.

After a stint on Broadway, Harper made his television debut as Detective Bert Kling on NBC's police procedural 87th Precinct from 1961 to 1962. The series, based on novels written by Ed McBain, also starred Norman Fell, Robert Lansing, Gregory Walcott and Gena Rowlands.

Shortly after, he nabbed the part of Jeff Conway, husband to Connie Stevens' titular character, in Wendy and Me. His time on the series was short-lived, the sitcom ran on ABC from 1964 to 1965. His 15-year-long career in television proceeded with his roles in CBS' The Jean Arthur Show in 1966 and ABC's Garrison's Gorillas in 1967.

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In 1974, Harper was cast as astronaut Alan Virdon on Planet of the Apes. The series, which came shortly after the 1968 original Planet of the Apes film, was canceled after 14 episodes.

Harper later took on the role of Uncle Jack in NBC's Land of the Lost in 1976 for its third and final season.

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In a 2005 interview for the series' bonus features, Harper revealed that his daughter was a big fan of the Land of the Lost series.

"The stories were very good,” he explained. “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 I’ve been showing them to my daughter since she was 5. And she still, of all my series, loves Land of the Lost best.”

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