I feel this needs some explanation:
Back in the day, the editor in chief at DC, Julius Schwartz, had an opinion...
If you wanted to boost sales on any given comic, put a gorilla on the cover.
Weirdly, the sales stats seemed to back him up and so throughout the late 50s and 60s, a BUNCH of primate related covers turned up across all of DC.
"I followed every single magazine that we produced and I was able to see how certain themes would sell. For example, I discovered that gorillas sell. We had gorilla covers on Star Spangled War Stories or Wonder Woman - you name a magazine, we had a gorilla on it. You know what happened? Sales exceeded our expectations."
https://screenrant.com/dc-comics-history-gorillas-apes-covers-silver-age/
"In the period of 1951-1970, Julius Schwartz oversaw a total of 22 ape covers on books he edited, followed by the editor of all Superman titles Mort Weisinger with 18. Jack Schiff, who handled a wide variety of books including Batman (and co-created Batman's Bat-Signal) oversaw 17 ape covers in this period."