The Case of the Female Orgasm: Bias in the Science of Evolution (review)

Methodical and lucid, Elisabeth Lloyd's The Case of the Female Orgasm: Bias in the Science of Evolution is an exemplar of accessible science writing.¹ Those interested in evolutionary biology, philosophy of science, and feminism will find the book an interesting, if perhaps occasionally frustrating, read. Although at times Lloyd's clear and detached account is somewhat dry, it seems strategic in the field of evolutionary biology where feminist scholarship is sometimes greeted with suspicion and contempt (witness David Barash's extraordinarily vicious review of the book [2005]² ). Lloyd offers a rigorous case study showing how political and methodological biases have distorted the practice and results of evolutionary investigations of female orgasm. Androcentrism and adaptationism bear the brunt of her attack, though heterosexism and the assumption of human uniqueness also play a role, albeit marginal. Though focused on critique, her argument is by no means wholly negative; Lloyd defends Donald Symons's evolutionary by-product account of female orgasm (1979), and suggests that negative biases can be avoided by employing Helen Longino's standards for how scientific communities can support objective inquiry (1993, 2002). Feminist scholars will find the book useful as a clear and persuasive contemporary case study in which androcentric bias has produced bad science, but beyond this point, the book's contribution is more ambiguous. From a feminist perspective, Lloyd leaves undeveloped some of the most interesting issues, including the social significance of the science of orgasm, the adequacy and limitation of sexology data in the description of orgasm, and the role of feminist approaches to science beyond merely controlling for sexist bias, in other words, beyond naïve feminist empiricism.

Being a case study, the book is rather thin on philosophy, which is relegated to the first and last chapters. The first chapter introduces important conceptual tools and the standards of evidence used in evolutionary explanations, which Lloyd carefully employs in later chapters. The majority of the book exhaustively reports the sexological data concerning female orgasm and its association with reproductive fitness and critically examines twenty-one evolutionary theories about the function of female orgasm. Lloyd points out in her review of the sexology research that although this data is inevitably flawed—distorted by poor definitions, sampling problems, and the limitations of self-reporting—it is still the only available empirical base to which any scientific theory must be accountable. She persuasively argues that the data show a weak correlation between female orgasm and intercourse—the orgasm/intercourse discrepancy—and a wide variation of orgasmic response, which prima facie suggests a lack of selection pressures shaping it. This grounds what is perhaps the most compelling feature of the book—Lloyd's demonstration that the vast majority of research into the evolution of the female orgasm simply ignores or misinterprets the data (sometimes while even citing it), thus failing the most basic scientific test of empirical adequacy.

In chapters 3, 4, and 7, Lloyd provides a forty-year overview of theories that scientists have proffered to explain the evolution of female orgasm and demonstrates how adaptationist and androcentric biases have rendered them inadequate. Chapter 3 surveys the theories that explain the evolution of female orgasm by attributing to it the function of supporting pair-bonding (in females only—males remain philanderers). Chapter 4 surveys other just-so stories (including female-centered explanations) that, while not depending on pair-bonding, fall prey to much the same criticisms. Chapter 7 focuses on sperm selection accounts that contemporary evolutionary biologists currently favor.

In chapter 6, Lloyd provides a discussion of adaptationism that gives both some useful background and conceptual clarification. While the devil is in the details, roughly speaking, adaptationism is the view that natural selection determines the form and function of a biological trait; in other words, a trait exists because it...