Thanks to Usual John for suggesting this and providing useful discussion.

How does the mention of the dino’s penguin diet prompt that change of mind about imminent danger? Of extinction? I don’t understand.
Usual John adds “Incidentally, but presumably not germane to the joke, armored dinosaurs like this one were usually herbivorous. I’m not sure what kind it is supposed to be (Johnny Hart probably did not know either, but he likely was basing it on a picture or museum specimen he had seen). Maybe a stegoceras? Not the better-known stegosaurus, since there is no thagomizer.”
“Note that this would have been before the current understanding that birds are modern dinosaurs was widely accepted and also before it occurred to anyone that (non-avian) dinosaurs were killed off by an asteroid.”























