Earlier, I posted a panel from an inane Atlas book wherein dogs are believed to be setting themselves up as mankind's replacements. Unbelievably, this was actually a recurring plot in Atlas Comics!
The above hails from Marvel Tales#133 (1955): "The Talking Dog" (art by Bob Powell). In this tale, a man discovers his dog can talk; the dog claims his species learned speech before humans and have secretly guided mankind down the centuries. The owner is outraged at the idea and tries to exploit his dog's power of speech, but the dog ends up running away, regretting have shared the information.
Two years later we have Astonishing#59 (1957): "Who is the Master?" (art by Robert Q. Sale). This time a scientist believes his dog possess psychic powers and have malevolent plans to surpass humans, conquering the Earth. He goes after his dogs with a gun but neither he nor the dogs are seen again. *dramatic stinger*
Finally, in Journey into Mystery#62 (1960): "There is a Brain Behind the Fangs!" (art by Don Heck). This is easily the silliest of the lot. Allow me to repeat the above dialogue:
"But Frank, there is no evidence that dogs have been getting smarter!"
"That's right -- and that's why I say they're a menace! They have been developing but they haven't revealed it!"
I'm sure I've seen the latter person in various internet forums. In this outing, the dogs turn out to be the servants of the real brains behind mankind's downfall: the cats! Seriously.
Perhaps these stories were ripping off a popular science fiction pulp magazine tale (Atlas frequently plagiarized the pulps). I do think it interesting, though, to wonder why creators of the 1950s would set up dogs as a potential threat. Was it an outgrowth of HUAC and McCarthyism, encouraging US citizens to distrust everyone, even the gentlest most inoffensive creatures? Was it a reaction against the rigid conformity of 1950s culture, suggesting an underlying menace within the nuclear family's own backyard? Or was it the byproduct of extremely disenchanted hacks trying desperately to fill up comic book pages so they could afford sending their kids to school? The truth is out there.