There's gotta be an answer.
3 seconds sound clip from the Planet of the Apes (1968) movie soundboard.
You can hear this line at 01:46:45 in the Blu-ray version of the movie.
Quote context
[...]
- What evidence? There were no weapons in that cave.
- The Forbidden Zone was once a paradise.
- Your breed made a desert of it ages ago.
- It still doesn't give me the why.
- A planet where apes evolved from men?
- Don't look for it, Taylor. You may not like what you find.
- No, no, no. Wait! Wait! Let him go.
- Lieutenant, fetch our explosives. We're going to seal up the cave.
[...]