Why did the Captain want Spender to escape?

Spender is the archaeologist for the fourth exped quickly leaves the crew to explore the planet by himself. He learns to read Martian. Finally, he decides that he should kill off the crew in an effort to preserve Mars.

Explanation:

i think it's either 'to expose the corruption of the communists in russia', or 'to criticize animal brutality by communists in russia.'  

hope this ! : )

pulling in the reader is important