Rethinking Human Culture: Cognitive Mechanisms and Cross-Species Continuities

Culture is often portrayed as a uniquely human hallmark, framed in symbolic and interpretive terms that lack mechanistic grounding and allow the concept to encompass almost anything. However, the species with the most cognitively elaborate cultures outside humans—chimpanzees and orcas—show that culture is not a human-exclusive construct, but a continuous process grounded in general cognitive scaffolds. This perspective calls for a definition that is precise enough to be mechanistically testable while unified enough to apply universally across cultural phenomena. We therefore propose: culture is group behaviour transmitted and maintained across time, supported by two continuous spectra of cognitive substrates: (1) individual-level social learning, from simple imitation to  explicit teaching, and (2) group-level processes, from non-inferential matching to structured, intentional transmission. We further show that species with greater cognitive capacities occupy broader ranges on these spectra, engaging in more complex and cognitively demanding cultural behaviours. This framework replaces symbolic assumptions with mechanistic structure, offering a unified account of cultural stability, variation, and graded complexity across contexts.