Man, I'd love to run across a book illustrated by Charley Harper during one of my thrift store excursions. His style is instantly recognizable to fans of Golden Books, and he's one of my favorite mid-century illustrators. His birds are especially cool, taking his "minimal realism" to an extreme, breaking them down to their simplest shapes. Here's a relevant sample of his work from 1961's The Giant Golden Book of Biology, chock-full of paleo yummies.
Image from Grain Edit, via flickr.
More: a Grain Edit post on this Golden title, the official site of the Charley Harper estate, and interview with Harper by the Cornell Laboratory of Ornithology.