Symons, Donald

Donald Symons (born 1942) is an American anthropologist whose work has been instrumental in shaping the field of evolutionary psychology. His seminal book, The Evolution of Human Sexuality (1979), is widely regarded as a foundational text, establishing a framework for understanding human sexual behavior through the lens of Darwinian natural selection. Symons's approach emphasized that human psychology, including sexual desires and preferences, is composed of evolved adaptations designed to solve recurrent problems faced by our ancestors in the ancestral environment.

Intellectual Contributions

Symons's primary contribution was to systematically apply the principles of evolutionary biology, particularly sexual selection theory, to explain the universal patterns and sex differences observed in human mating. Prior to his work, much of the academic discourse on human sexuality either emphasized cultural determinism or adopted a sociobiological perspective that sometimes conflated genetic interests directly with behavior, without fully articulating the intervening psychological mechanisms. Symons argued for the existence of domain-specific psychological adaptations that mediate between evolutionary pressures and observable behavior.

The Evolution of Human Sexuality (1979)

In this landmark work, Symons challenged prevailing social science paradigms that viewed human sexuality as largely a product of culture or learning, or as a undifferentiated drive. He posited that male and female sexual psychologies have diverged due to differing reproductive challenges and opportunities. For men, reproductive success was historically limited by access to fertile mates, leading to evolved desires for sexual variety and cues to female fertility (e.g., youth and health). For women, reproductive success was historically limited by access to resources and parental investment, leading to evolved preferences for mates who could provide resources and protection. Symons argued that these evolved psychological mechanisms, rather than conscious calculations of genetic fitness, drive human sexual behavior.

Key arguments from the book include:

• Sex Differences in Parental Investment: Drawing on Trivers's (1972) theory of parental investment, Symons explained how the fundamental asymmetry in minimum parental investment (sperm is cheap, eggs are expensive, gestation is long) leads to divergent sexual strategies. Males, with lower minimum investment, are predicted to be more eager for sexual encounters, less discriminating in mate choice for short-term liaisons, and more prone to jealousy over sexual infidelity. Females, with higher minimum investment, are predicted to be more selective in mate choice, to prioritize resource-provisioning ability in long-term partners, and to be more concerned with emotional infidelity (which might signal resource diversion).
• The Role of Psychological Mechanisms: Symons stressed that evolved adaptations are psychological mechanisms—specific information-processing devices—not merely behavioral propensities. For example, male sexual jealousy is not just a behavior, but an evolved psychological mechanism designed to protect paternity certainty by detecting and deterring mate poaching.
• Distinction between Desire and Behavior: He emphasized that evolved desires and preferences do not dictate behavior in a deterministic way. Environmental and cultural factors can modulate the expression of these desires. Moreover, evolved desires are not necessarily consciously understood or rationally chosen; they are often felt as urges or attractions.
• Critique of the Standard Social Science Model: Symons was an early and forceful critic of the then-dominant view in social sciences that human minds are largely blank slates, shaped primarily by culture. He argued that this perspective failed to account for cross-cultural universals and the deep-seated nature of many sex differences in sexual psychology.

Impact and Influence

Symons's work, alongside that of other pioneers like Margo Wilson and Martin Daly, John Tooby and Leda Cosmides, provided much of the conceptual bedrock for the emerging field of evolutionary psychology in the 1980s and 1990s. His rigorous application of evolutionary theory to human behavior, particularly his focus on psychological mechanisms, helped to define the field's distinct identity, differentiating it from earlier forms of sociobiology. His influence is evident in subsequent research on mate preferences, sexual jealousy, infidelity, and the evolutionary origins of sexual orientation.

Critiques and Debates

While highly influential, Symons's work has also faced criticism. Some critics, such as Buller (2005), have argued that Symons, and evolutionary psychology more broadly, sometimes overemphasizes genetic determinism or offers post hoc explanations without sufficient empirical rigor. Others have questioned the extent to which observed sex differences are truly universal or are more plastic and influenced by socio-cultural factors than Symons's framework might suggest. For instance, some feminist scholars have argued that evolutionary explanations for sex differences in sexuality can be used to justify existing gender inequalities.

Symons himself has consistently maintained that evolved psychological mechanisms provide a basis for understanding human behavior, but that these mechanisms interact complexly with environmental and cultural inputs. He has also been a proponent of the view that evolutionary psychology should focus on mapping the universal architecture of the human mind, rather than explaining individual differences, which he views as largely a product of non-adaptive genetic variation or environmental factors.

Despite ongoing debates, Symons's contributions remain central to the study of human sexuality from an evolutionary perspective. His work continues to stimulate research and discussion, providing a powerful framework for understanding one of the most fundamental aspects of human experience. His insistence on a psychological level of analysis, distinct from both genetic and behavioral levels, has been a lasting legacy in the field of evolutionary psychology.