Beyond falsifiability: Evolutionary psychology's many theoretical strengths-Reply to Geary (2026) and Moore (2026)

We thank Moore (2026) and Geary (2026) for their thoughtful commentaries on Costello et al. (2026). Both agree on our core premise: that evolutionary psychology's hypotheses are falsifiable. We hope this shared recognition can help finally dispel the mistaken claim that evolutionary psychology is inherently unfalsifiable. Moore rightly notes that "falsifiability is a necessary but insufficient quality of a good scientific theory" (Moore, 2026, p. 29). We agree and note that evolutionary psychology exhibits many other hallmarks of good theory. It triangulates converging evidence for psychological adaptations that withstand empirical scrutiny across diverse contexts. It uncovers human universals and explains cross-cultural variation. It has powerful heuristic value, guiding researchers to novel domains of discovery. It helps make sense of otherwise anomalous findings. Contrary to Moore's characterization of the field as "narrow" (Moore, 2026, p. 29), one of evolutionary psychology's greatest strengths is cross-disciplinary consilience: the ability to integrate the disparate subfields of the human behavioral sciences under the same overarching evolutionary theory that unifies all of the life sciences. If another metatheory for psychology exists that possesses these many theoretical strengths, it has not been made known to the scientific community (see Buss, 2020, for an overview of evolutionary psychology's theoretical strengths). We focus here on evolutionary psychology's heuristic value, before addressing Moore's view that the ultimate evolutionary level of analysis is superfluous to developmental explanations. We end by highlighting the practical utility of the functional level of analysis for understanding both human biology and psychology. (PsycInfo Database Record (c) 2026 APA, all rights reserved).