Social Darwinism has, almost indelibly, tainted most people’s understanding of evolutionary theory-certainly as it applies to human beings. Yet social Darwinism differs from Darwinism-without-adjectives in one all-important way, and ignoring this distinction has been one of the most unfortunate and long-lived mistakes of science journalism. Darwinism proper is devoted to analyzing all the diverse forms of life according to the theory of natural selection. Darwinists describe competition between unequal individuals, but they place no value judgment on either the competition or its outcome. Natural-selection theory provides a powerful way to understand the subordination of one individual, or group of individuals, by another, but it in no way attempts to condone (or condemn) subordination.
By contrast, social Darwinists attempt to justify social inequality. Social Darwinism explicitly assumes that competition leads to “improvement” of the species; the mechanism of improvement is the unequal survival of individuals and their offspring. Applying this theory to the human condition, social Darwinists hold that those individuals who win the competition, who survive and thrive, must necessarily be the “best.” Social inequalities between the sexes, or between classes or races, represent the operation of natural selection and therefore should not be tampered with, since such tampering would impede the progress of the species. It is this latter brand of Darwinism that became popularly associated with evolutionary biology. The association is incorrect, but it helps to explain why feminists have steadfastly resisted biological perspectives.
~Sarah Blaffer Hrdy, The Woman That Never Evolved, p. 12-13