Masters of Evolution is a 1959 science fiction

Science fiction

Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...

 novel by Damon Knight

Damon Knight

Damon Francis Knight was an American science fiction author, editor, critic and fan. His forte was short stories and he is widely acknowledged as having been a master of the genre.-Biography:...

. It first appeared in 1954 in Galaxy Science Fiction

Galaxy Science Fiction

Galaxy Science Fiction was an American digest-size science fiction magazine, published from 1950 to 1980. It was founded by an Italian company, World Editions, which was looking to break in to the American market. World Editions hired as editor H. L...

as the novella "Natural State". Knight subsequently expanded the text by about 5000 words, and the longer version was published by Ace Books

Ace Books

Ace Books is the oldest active specialty publisher of science fiction and fantasy books. The company was founded in New York City in 1952 by Aaron A. Wyn, and began as a genre publisher of mysteries and westerns...

 in 1959 as Masters of Evolution, in a dos-a-dos

Dos-à-dos binding

In bookbinding, a dos-à-dos binding is a binding structure in which two separate books are bound together such that the fore edge of one is adjacent to the spine of the other, with a shared lower board between them serving as the back cover of both...

 paperback that included George O. Smith

George O. Smith

George Oliver Smith was an American science fiction author. He is not to be confused with George H. Smith, another American science fiction author.-Biography:...

's Fire in the Heavens (Ace Double D-375).

Synopsis

In the near future, the world is divided into two antagonistic groups: city dwellers and country dwellers, called "muckfeet". The muckfeet control most of the land area and have a much higher population. The mayor of New York convinces a popular actor, Alvah Gustad, to negotiate an agreement with the muckfeet: technology in exchange for their scarce metals. Alvah reluctantly agrees, and is given a chance to present his wares at a fair in the Midwest. No one is interested; an altercation ensues and Alvah realizes that he is stranded. He is taken in by a pretty young woman named B. J.; gradually he comes to accept and understand the muckfeet way of life, which includes novel uses of genetic engineering in place of machines. Alvah falls in love with B. J. and when the cities launch an attack on the muckfeet, Alvah is forced to reexamine his beliefs about the superiority of the city way of life.