BANANAS!

Why is it when someone is acting silly or out of their mind, we say "They've gone BANANAS!"?

The Cobbler posited that there is some unknown cultural reference, like a film or a tv show, that has been lost on us.

I think it is because it is a reference to a more "perimative version of a human". The monkey is a great non-scientific way of referring to an uncivilized human who does silly things and acts in a strange way based on its humanoid body type and presence of an intelligence but not one as advanced as humans. By the way, this is not science logic, just unsupported conjecture.

The internet has given me some other answers.

Many of the articles I read refer to the earliest usage as an isolated incident in the 1930's when Albin Jay Pollock used the phrase in The Underworld Speaks. Here, bananas was used by gangsters to describe an individual as sexually perverted or a degenerate. The Online Etymology states that it was not until 1968 that the word was used as a synonym for crazy. One article says it stems from the phrase "going ape" or from an observation of when a group of apes was given bananas, they ate them with "tremendous enthusiasm". My favorite alternative is that it comes from a rumor that was spread across university campuses in the late 1960's which stated that "roasted banana peels had psychedelic properties, and that ingesting them could lead to hallucinations similar to ones brought on by LSD or psilocybin mushrooms." (This is not true, by the way)

Who know what the real origins of this phrase are? We do know that it began to be popularized in the early 1970's and reached a high point in the 80's. I'm actually not sure how common this phrase is anymore, what with all the "new lingo" that the youths use nowadays. I, however, plan to use it with slight to medium frequency.

Sources:

https://www.etymonline.com/search?q=bananas

https://blog.oxforddictionaries.com/2014/08/01/origin-banana/

https://english.stackexchange.com/questions/74581/why-does-bananas-mean-crazy

http://discovolonte.typepad.com/discovolonte/2007/12/the-mystery-of.html

http://www.englishdaily626.com/slang.php?054

#BANANA