Components of evolutionary psychology are falsifiable, but does that make it a good theory? Commentary on Costello et al. (2026).

At the center of narrow evolutionary psychology's theory lies the assumption that many human behavioral mechanisms evolved via natural selection. Although some components of this theory are falsifiable, its Lakatosian framework protects its core assumptions from falsifiability, even though most human behaviors probably do not require evolutionary explanations. Crucially, falsifiability is a necessary but insufficient quality of a good scientific theory, and the value of narrow evolutionary psychology can be questioned on other grounds. Narrow evolutionary psychology holds that only natural selection can create complex, functional adaptations, but natural selection is not a creative force; this process merely functions as a sieve that influences phenotype frequencies in descendant populations. Instead, only developmental processes can create the adaptations observed in individuals. Evolutionary explanations for behaviors will always be less useful than developmental explanations, given the context-dependent, emergent, and plastic nature of development. Evolutionary explanations will often be superfluous. (PsycInfo Database Record (c) 2026 APA, all rights reserved).