dualinheritance

Dualinheritance, or dual inheritance theory, is an interdisciplinary framework that posits humans inherit information through two distinct channels: genetic inheritance and cultural inheritance. Genetic inheritance transmits biological traits via DNA, while cultural inheritance disseminates ideas, practices, and artifacts through social learning. These two systems interact in shaping behavior, development, and evolution. Cultural evolution is driven by variation, transmission, and selection of cultural traits, which can spread rapidly compared to genetic changes.

Culture is transmitted through multiple pathways: vertical transmission from parents to offspring, horizontal transmission between peers, and oblique transmission from older to younger individuals who are not their offspring. Cultural traits can be biased by prestige, conformity, payoff, or success, affecting their likelihood of spread. Gene-culture coevolution describes how cultural practices create selection pressures on genetic variants and vice versa, leading to intertwined evolutionary dynamics.

Origins and development: the framework was formalized in the works of Robert Boyd and Peter Richerson in the 1980s, drawing on earlier ideas about cultural transmission. It has been extended by researchers like Cavalli-Sforza and others and remains influential in anthropology, psychology, and evolutionary biology. Common research topics include language, technology, social norms, and subsistence strategies. Case studies such as lactose tolerance in dairy-farming populations illustrate gene–culture coevolution, while norms around cooperation illustrate cultural evolution.

Criticisms center on measurement challenges, definitional ambiguity, and the risk of explanatory circularity; some argue for more explicit models or alternative frameworks. Despite debates, dualinheritance provides a structured way to analyze how genetic and cultural processes interact to shape human behavior and the evolution of populations.