The Descent of Man, and Selection in Relation to Sex is a book by English naturalist Charles Darwin, first published in 1871, which applies evolutionary theory to human evolution, and details his theory of sexual selection, a form of biological adaptation distinct from, yet interconnected with, natural selection. The book discusses many related issues, including evolutionary psychology, evolutionary ethics, differences between human races, differences between sexes, the dominant role of women in mate choice, and the relevance of the evolutionary theory to society. From Wikipedia (CC BY-SA).

Babbitt, first published in 1922, is a novel by Sinclair Lewis. Largely a satire of American culture, society, and behavior, it critiques the vacuity of middle-class American life and its pressure toward conformity. An immediate and controversial bestseller, Babbitt was influential in the decision to award Lewis the Nobel Prize in literature in 1930. The word "Babbitt" entered the English language as a "person and especially a business or professional man who conforms unthinkingly to prevailing middle-class standards". From Wikipedia (CC BY-SA).