Richerson et al. give compelling evidence that the conditions for Darwinian evolution are sometimes met in the case of cultural groups. By presenting evidence for cultural group variation, inheritance, and selection, the authors succeed in rendering the cultural group selection (CGS) hypothesis more plausible, and we agree that CGS may partly explain cooperation and other cultural traits. We remain unconvinced, however, that the evidence demonstrates that CGS is a particularly strong force in cultural evolution because selection mechanisms – conquest, imitation, and migration – frequently do not involve selection between cultural groups, but instead work at the level of individual cultural traits.
Consider a case where the conditions favorable to CGS are met: Distinct cultural groups compete, and a group achieves greater success due to cultural variation. According to CGS, we should expect the cultural traits underpinning that group's success to spread. Presumably, such transmission occurs either by complete assimilation to the successful group or by selective adoption of traits, with preference for traits specifically contributing to competitive success.
Total transmission is rarely the case. Even when it is clear that selective conquest, migration, or imitation has occurred, these selective forces rarely involve the total replacement of all the features of the less successful group with all the features of the more successful group. Instead, cultural groups in competitive situations adopt only some features of competing groups, or more frequently, new hybrid cultural traits emerge through the fusion of features from multiple groups. In any particular case, there are various potential reasons for why one trait, and not another, was adopted after a process of conquest, imitation, or migration. While CGS may be a factor, we can also appeal to other factors not accounted for by CGS, including the direct appeal of that trait or pure chance. To be convinced that CGS is a strong force in cultural evolution, we need evidence that cultural borrowing in cases of conquest, imitation, and migration is predominantly driven by contribution to group-level differential success, and not by other potential explanations.
We speculate that CGS is not among the strongest forces driving which cultural traits spread in such cases. To see why, let us examine a paradigmatic case. The authors (Richerson et al.) consider the spread of religion as a flagship case of CGS, noting that features of Christianity contributed to the success of Christian groups, so those cultural features spread both through successful conquest and through comparative success in situations of resource scarcity. A closer inspection, however, calls this story into question. The spread of a religion does not entail the spread of all its cultural features. On the contrary, it has long been recognized that the spread of religion in the face of differential success of cultural groups involves syncretism, defined as “a type of acceptance characterized by the conscious adaptation of an alien form or idea in terms of some indigenous counterpart” instead of the replacement of the indigenous trait by the foreign one (Madsen Reference Madsen and Wauchope1967, p. 369). Consider the spread of Roman Catholicism to what is now Mexico. Invading European cultural groups out-competed the pre-Columbian cultural groups of Mexico, and part of the conquest involved the adoption of Catholicism by native groups. The adoption, however, was syncretic – the surface trappings of Catholicism became part of local culture, but indigenous groups were selective about which Catholic practices they adopted, and also selectively retained native practices by giving them a nominally Catholic guise. Well-known examples include the retention of indigenous holidays such as Día de Muertos, the continuance of traditional practices such as curanderismo, and the thinly-veiled re-presentation of indigenous deities as Catholic saints such as La Virgen de Guadalupe.
How does syncretism of this sort tell against CGS? Syncretism demonstrates that the spread of a religion due to the dominance of a cultural group does not entail the successful reproduction of any particular aspect of the cultural systems associated with that group. Although, for instance, Mayan communities adopted the practice of saint worship from the conquering Spanish, Mayan saint worship tends to “evince a more profound parochialism than did saint worship in 16th-century Spain. Cosmologically, Maya saints have become decidedly local personages relatively independent of the remote … God” (Watanabe Reference Watanabe1990, p. 137). This is telling. The conquest of New Spain was facilitated by the parochialism of indigenous cultural groups; the fractious independent city states of Mexico could not compete with a nation-state built around a common identity. Nevertheless, this cooperative feature of Spanish Catholic culture was resisted by many of the conquered peoples, even while cultural traits irrelevant to differential success (e.g., the names of deities) were adopted. In short, the veneer of Catholicism spread, but for CGS, it is not the veneer that matters, but rather the values and practices which contributed to differential group success. Which values and practices were adopted, however, seems to have little to do with whether they contributed to success, but instead with how those practices individually appealed to the conquered peoples.
Other cases of the spread of religion by conquest, imitation, and migration exhibit the same pattern, as do, we would argue, cases of cultural transmission in other domains. To a large degree then, which cultural traits spread in cases of differential competitive success is explained by factors other than the role those traits played in that success. To determine the relative strength of CGS in relation to other cultural evolutionary forces, we need not only to establish that conditions favorable to CGS are met, but also to examine particular instances of cultural transmission. This would involve systematically sampling traits from the more successful cultural system, then determining for each individual sample whether it spread and, if so, the extent to which CGS contributed. By establishing a theoretical background against which we can perform this sort of investigation into the contributions of CGS to the evolution of human cultural traits, Richerson et al. open the doors to research that may help us better understand many of the most notable features of culture.
You have
Access
Richerson et al. give compelling evidence that the conditions for Darwinian evolution are sometimes met in the case of cultural groups. By presenting evidence for cultural group variation, inheritance, and selection, the authors succeed in rendering the cultural group selection (CGS) hypothesis more plausible, and we agree that CGS may partly explain cooperation and other cultural traits. We remain unconvinced, however, that the evidence demonstrates that CGS is a particularly strong force in cultural evolution because selection mechanisms – conquest, imitation, and migration – frequently do not involve selection between cultural groups, but instead work at the level of individual cultural traits.
Consider a case where the conditions favorable to CGS are met: Distinct cultural groups compete, and a group achieves greater success due to cultural variation. According to CGS, we should expect the cultural traits underpinning that group's success to spread. Presumably, such transmission occurs either by complete assimilation to the successful group or by selective adoption of traits, with preference for traits specifically contributing to competitive success.
Total transmission is rarely the case. Even when it is clear that selective conquest, migration, or imitation has occurred, these selective forces rarely involve the total replacement of all the features of the less successful group with all the features of the more successful group. Instead, cultural groups in competitive situations adopt only some features of competing groups, or more frequently, new hybrid cultural traits emerge through the fusion of features from multiple groups. In any particular case, there are various potential reasons for why one trait, and not another, was adopted after a process of conquest, imitation, or migration. While CGS may be a factor, we can also appeal to other factors not accounted for by CGS, including the direct appeal of that trait or pure chance. To be convinced that CGS is a strong force in cultural evolution, we need evidence that cultural borrowing in cases of conquest, imitation, and migration is predominantly driven by contribution to group-level differential success, and not by other potential explanations.
We speculate that CGS is not among the strongest forces driving which cultural traits spread in such cases. To see why, let us examine a paradigmatic case. The authors (Richerson et al.) consider the spread of religion as a flagship case of CGS, noting that features of Christianity contributed to the success of Christian groups, so those cultural features spread both through successful conquest and through comparative success in situations of resource scarcity. A closer inspection, however, calls this story into question. The spread of a religion does not entail the spread of all its cultural features. On the contrary, it has long been recognized that the spread of religion in the face of differential success of cultural groups involves syncretism, defined as “a type of acceptance characterized by the conscious adaptation of an alien form or idea in terms of some indigenous counterpart” instead of the replacement of the indigenous trait by the foreign one (Madsen Reference Madsen and Wauchope1967, p. 369). Consider the spread of Roman Catholicism to what is now Mexico. Invading European cultural groups out-competed the pre-Columbian cultural groups of Mexico, and part of the conquest involved the adoption of Catholicism by native groups. The adoption, however, was syncretic – the surface trappings of Catholicism became part of local culture, but indigenous groups were selective about which Catholic practices they adopted, and also selectively retained native practices by giving them a nominally Catholic guise. Well-known examples include the retention of indigenous holidays such as Día de Muertos, the continuance of traditional practices such as curanderismo, and the thinly-veiled re-presentation of indigenous deities as Catholic saints such as La Virgen de Guadalupe.
How does syncretism of this sort tell against CGS? Syncretism demonstrates that the spread of a religion due to the dominance of a cultural group does not entail the successful reproduction of any particular aspect of the cultural systems associated with that group. Although, for instance, Mayan communities adopted the practice of saint worship from the conquering Spanish, Mayan saint worship tends to “evince a more profound parochialism than did saint worship in 16th-century Spain. Cosmologically, Maya saints have become decidedly local personages relatively independent of the remote … God” (Watanabe Reference Watanabe1990, p. 137). This is telling. The conquest of New Spain was facilitated by the parochialism of indigenous cultural groups; the fractious independent city states of Mexico could not compete with a nation-state built around a common identity. Nevertheless, this cooperative feature of Spanish Catholic culture was resisted by many of the conquered peoples, even while cultural traits irrelevant to differential success (e.g., the names of deities) were adopted. In short, the veneer of Catholicism spread, but for CGS, it is not the veneer that matters, but rather the values and practices which contributed to differential group success. Which values and practices were adopted, however, seems to have little to do with whether they contributed to success, but instead with how those practices individually appealed to the conquered peoples.
Other cases of the spread of religion by conquest, imitation, and migration exhibit the same pattern, as do, we would argue, cases of cultural transmission in other domains. To a large degree then, which cultural traits spread in cases of differential competitive success is explained by factors other than the role those traits played in that success. To determine the relative strength of CGS in relation to other cultural evolutionary forces, we need not only to establish that conditions favorable to CGS are met, but also to examine particular instances of cultural transmission. This would involve systematically sampling traits from the more successful cultural system, then determining for each individual sample whether it spread and, if so, the extent to which CGS contributed. By establishing a theoretical background against which we can perform this sort of investigation into the contributions of CGS to the evolution of human cultural traits, Richerson et al. open the doors to research that may help us better understand many of the most notable features of culture.