Examining the Possibility of Maladaptive Cultural Evolution through Oblique Transmission

As one of the prerequisites for maladaptive cultural evolution, oblique transmission has drawn attention. However, even though maladaptive cultural evolution could occur if children choose oblique transmission frequently, can oblique transmission be selected by children in the course of genetic evolution? In addressing the question above, in this study, we conducted agent-based simulations focusing on the evolution of “oblique transmission bias,” the tendency of children to choose oblique transmission when they can choose between oblique and vertical transmission. At first, we analyzed how the oblique transmission bias evolves by comparing models with two cultural traits versus five traits, manipulating the probability of environmental changes and the strength of natural selection, respectively. As a result, the oblique transmission rate evolved under limited conditions. Second, we conducted simulations under the setting of the oblique transmission rates as exogenous variables; maladaptive cultural evolution did not occur because of oblique transmission when oblique transmission bias is as strong as one evolved in the previous simulation. In addition, we show that if maladaptive culture is more likely to be imitated by children, maladaptive cultural evolution occurs.