Trivia

1. Time dilation is the difference in time measurement between two observers. Time runs at different rates depending on the relative velocity between the observers. Time dilation has been experimentally proven.
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Edward G. Robinson was originally slated to play Dr. Zaius but he dropped out due to health concerns and a reluctance to endure the transformations over a period of months.
--Source: Planet of the Apes: An Unofficial Companion, Page 9

Writer Pierre Boulle was greatly upset by the ending. "I have come to consider it as a temptation from the devil." In the original story, the spacecraft crew does land on another planet, 350 light years from Earth. The main character, Ulisse (Taylor in the film) escapes from the ape authorities with Nova, and they return to Earth, after another 350 light years, only to find that Earth has undergone the same evolution.
--Source: Planet of the apes: an unofficial companion, Page 21

The concluding beach scenes were filmed on a remote beach with cliffs that towered 130 feet above the shore. Reaching it on foot was very difficult, so cast, crew, film equipment, and even horses had to be lowered in by helicopter.
--Source: Planet of the Apes Revisited, Page 79

The sequels:Beneath the planet of the apes (1970)Escape from the planet of the apes (1971)Conquest of the planet of the Apes (1972)Battle for the planet of the Apes (1973)

Writer Pierre Boulle (French novelist) actually considered the novel one of his lesser works. He liked his earlier book The bridge on the river Kwai.

In the novel (1963, original title La Planète des singes) the apes are technologically very advanced. However, the budget could not accommodate the visual scope and magnitude of such a futuristic society, so a more primitive depiction of ape society was used.

Director Tim Burton: The 2001 version is neither a remake or sequel.

In the 2001 ’remake’ Charlton Heston plays an old ape.

In 1969, Twentieth Century-Fox wanted Heston to return as the starring role in Beneath the planet of the apes. Heston didn't want to commit to a sequel, but agreed to make a brief appearance so long as his character was killed off early in the film. It was decided that he would act briefly in the beginning of the movie, and towards the end of the film for the movie's climax.

The encyclopedia says about Ape:Any primate of the subfamily Hominoidea. Apes vary in size from the 3 ft (90 cm) gibbon to the 6 ft (1.8 m) gorilla.
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